Peter Stuifzand

Don't Use AI for Writing

Sun, 02 Aug 2026 23:43:08 +0200

Writing is a useful skill to develop. It can help you discover what you think, develop judgment, and become a critical thinker. Writing can also be pleasurable in itself. You can feel the ownership of the results of your writing.

AI is there as a sharp contrast to us as beginners of writing. The ease with which AI generates plausible and polished text is attractive. The pressure to take the shortcut and have AI suggest ideas, rewrite your text, or generate it whole, can be hard to resist and it is the biggest barrier for us to keep developing our writing skills.

Doing Things Badly

Sun, 02 Aug 2026 15:54:50 +0200

If a thing is worth doing, it is worth doing badly.
– G.K. Chesterton

This quote shows that we need room to do things badly.

I read this quote in a book about writing essays. So I thought how am I going to brainstorm about this idea. I opened TLdraw and wrote the quote in a rectangle. My next thought was to use a different tool, with which I could brainstorm more efficiently: a mindmap or outliner.

Questions for Notes

Sun, 02 Aug 2026 15:38:41 +0200

I want to get more value from my Zettelkasten. When you see the notes as being part of a tree, then there are three directions to go: Up, Down, and Horizontal. Each direction has way to get more value by finding the questions and answers related to the current card.

Down is the easiest way to go. When you go down this means that you ask a question about the current card. Then you write new cards for each of the answers to that question.

Splitting Notes Branches

Sun, 17 Aug 2025 23:16:53 +0200

Splitting branches of notes too high up, makes installing notes more difficult.

Problem

I have a branch “1050 Critical Thinking” and the card has a definition. If I want to add another definition for critical thinking, I need to create a card “1050A Critical Thinking” with the new definition.

Now I need to think about installing new cards in the 1050 or the 1050A branch.

Solution

If I create the definition as a card below 1050, for example 1050/16, I can add the new definition as card 1050/16A. And furthermore all new cards can be placed under 1050.

My top-down method for expanding notes

Sun, 17 Aug 2025 21:31:15 +0200

Ever stare at your notes and wonder how to develop them further? I was reading The Pyramid Principle and it clicked for me. The book mentions the top-down approach for writing articles. You start with the main idea and then build up the argument. It seems to me that the Zettelkasten is also a good fit for this approach.

The Pyramid Principle uses inductive arguments. This means grouping multiple items of the same type under a plural noun like “claims”, “answers”, “steps”, or “consequences”. This creates a hierarchy that can be built top-down, starting with the main idea and then building up the supporting ideas. The Zettelkasten makes this possible by letting you start with a note and link the supporting notes to it.

Semantic versioning is outnumbered by inherent conflict

Fri, 15 Aug 2025 23:49:37 +0200

We version our code with Semantic versioning. Semantic versioning adds structure and rules for working with versions. Semantic versioning promises to solve the dependency hell problem. According to the website, dependency hell is that sometimes dependencies are specified too loosely, compatibility is assumed with too many future versions. When the dependency is too strict, you have to update the package to be able to use new version. And with version numbers following the rules, the promise is they will reliably communicate compatibility information.

Why I procrastinate by thinking about frameworks instead of sharing my opinions

Mon, 11 Aug 2025 23:50:53 +0200

When I take notes, I look at how I work and the workflows. I try to find how to take more and better notes. This makes me feel productive and competent. But this meta-work is also what keeps me safe. Why do I keep choosing meta-work over real work?

When I’m productive on the safe meta-level, I avoid the risks of the practical level. When I form and publish my opinions I take the risk that will lead to real competence.

How to transform your notes from dead storage to thinking partner

Sun, 27 Jul 2025 12:42:00 +0200

People take notes to remember and learn from what they read. They highlight the sections that interest them and comment on those notes. However, even when we take notes about our opinions about these highlights, we find ourselves with a big box of notes that don’t add to our lives. The notes exist as dead storage and gather dust.

How to prevent your notes from gathering dust and becoming dead storage?

By listening (in your mind) for the implied questions that a note suggests, you gain the opportunity to answer these questions. When you answer these questions, you gain understanding and collect new ideas and generate arguments to support other ideas. This process transforms your notes from dead storage to an active thinking partner.

AI attribution undermines professional accountability

Sun, 20 Jul 2025 22:34:54 +0200

AI tools like ChatGPT, Claude, and Gemini have changed how developers solve problems. We use them to debug complex issues, explore architectural patterns, and generate boilerplate code. These tools have become as much part of our workflow as Stack Overflow or documentation searches once were.

However, a troubling pattern has emerged in how we present AI-assisted research. Developers share content with disclaimers like “I asked ChatGPT and here’s what it said…” or “AI suggested this approach…” This attribution appears transparent but actually undermines professional responsibility.

Writing in Zettelkasten

Sat, 19 Jul 2025 21:21:49 +0200

I read the book The Pyramid Principle by Barbara Minto and specifically a section about how build to a pyramid structure from the bottom-up. She says that starting from the bottom-up is more difficult. I think that it is more difficult to start from the bottom, because you don’t have the raw materials.

The raw materials the ideas to build the structure. When you instead start from the top-down, you notice which (types of) ideas you are missing to answer the question from the note above.

My First Til

Sun, 06 Jul 2025 12:11:27 +0200

TIL how to use Gemini to write a template for TIL. It was possible, but I didn’t get the result I wanted. So in the end I used the templates from the other sections.

Counter, Tensor and View

Sat, 01 Feb 2025 23:15:12 +0100

The succ function can be called prod(max) times. The function can also be written with a carry or overflow “bit”. Then when i == len(counter) the return value should be counter, True. The return value of the last line, counter, False.

def succ(counter, max):
  i = 0
  counter[i] += 1
  while counter[i] == max[i]:
    counter[i] = 0
    i += 1
    if i == len(counter): return counter, i
    counter[i] += 1
  return counter, i

This function can be used to simulate multiple for-loops, where every element of max notes the number of loops. The i return value, shows which for-loop just overflowed. This can be used to simulate a step in that loop.

Hundred Year App

Sun, 03 Nov 2024 10:56:03 +0100

In the video Build the Hundred-Year Web Service with htmx Alexander Petros talks about how to build a hundred-year web service. He talks about how when you want to build, use and maintain a web app in a hundred, you should not have to ask permission to deploy your app.

I saw this video a few weeks after my apps were removed from Google Play Store. I had not made the changes to the app that were necessary to keep them on the Play Store.

Category of 3 bit binary numbers

Thu, 26 Sep 2024 09:32:01 +0200

Objects are three bit binary numbers. Morphisms exists when you can flip some bits from 1 to 0 (but not the other way around).

digraph G {

"000";
"001";
"010";
"011";

"100";
"101";
"110";
"111";

"001" -> "000";
"010" -> "000";
"100" -> "000";

"011" -> "001";
"011" -> "010";

"111" -> "101";
"111" -> "110";
"111" -> "011";

"101" -> "100";
"101" -> "001";
"110" -> "100";
"110" -> "010";
}

Streaming AI with htmx

Thu, 04 Apr 2024 07:00:00 +0100

Below is a simplified chat bubble for an conversation with an LLM.

This template is written in Templ and uses htmx to fill the chat bubble with incoming content. The incoming content is sent with SSE using the v2 version r3labs/sse Server Sent Events server. This version supports SplitData which makes it easier to sent the HTML for htmx. Adding a <span></span> around every token helps with the spaces in the tokens.

templ StreamingChatBubble(url string, message string) {
    <div>
        <span>user</span>
        <div>{{message}}</div>
    </div>
    <div
        hx-ext="sse"
        sse-connect={ url }
        sse-swap="done"
        hx-swap="outerHTML"
    >
        <span>assistant</span>
        <div
            sse-swap="message"
            hx-swap="beforeend"
        ></div>
    </div>
}

templ StreamingChatComplete(message string) {
    <div class="...">
        <span>assistant</span>
        <div>{{message}}</div>
    </div>
}

The url contains the SSE url with a stream parameter. The Go web server uses the code to find the right channel for updates. The updates to the channel are sent to the frontend. Each of the messages has a type. The messages with partial LLM response have the type message. And then when all partial responses are sent, the done message is sent with the complete chat bubble. This also removes the connection to the message channel.

Embeddings Similarity Search

Fri, 01 Mar 2024 21:06:13 +0100

For a simple note-taking application I wanted to try out embeddings and similarity search to find similar notes based on the content. In this post I will show how you how to use the gonum.org/v1/gonum/blas/blas32 package to calculate with embeddings.

Get your embeddings

When I started I used the OpenAI embeddings and saved these in the sqlite database with the notes themselves. At the moment I keep all embeddings in memory when the applications starts and new embeddings are added to the map when new notes are created or when notes are updated.

Deleting in Note Taking Apps

Mon, 18 Sep 2023 20:40:25 +0200

It seems I’m sentimental. I have difficulties with Archiving or Deleting documents from the Readwise Reader Inbox. I’m always looking at the conflicts in my live. and this seems to be one of them.

The problem in Readwise Reader is that I want to remove, or archive documents. But sometimes these documents contain something that I want to act on. If I Archive a document, I won’t see it again.

In Readwise it’s possible to create highlights, that can be resurfaced. For that you need to process your daily highlights. I did this for some time. But also the highlight is perhaps not enough to take action. Perhaps I should create projects and next-actions to take action, define an outcome and action steps. Would this be enough?

Apply TOC to highlighting, note-taking and knowledge gaps

Sat, 12 Aug 2023 16:25:01 +0200

The last few weeks I have been looking at Theory of Constrains (TOC). Today I noticed that with note-taking there is this conflict between just taking notes and taking notes to solve problems.

TOC is a management philosophy that emphasizes the identification and management of constraints that hinder an organization’s ability to achieve its goals. Instead of organizations you can also look at yourself and your systems and problems.

The Process of Ongoing Improvement in TOC involves five focusing steps:

Proconcloud method

Sat, 15 Jul 2023 09:04:14 +0200

Necessity assumptions

Why is it necessary?

Our attention is limited.
There is a gap between how well we make decisions and how well we can make decisions.
We want to make better decisions to be able to live a meaningful life.

Strategy

What for?

We want to avoid the following 5 decision mistakes.

Waste your limited attention
Suggest a solution prematurely or blame other people
Only try one solution, or use a compromise
Ignore valid reservations from stakeholders
Not learning from experience and performing the wrong experiments

Parallel assumptions

Why is it possible?

Strategy and tactics

Wed, 12 Jul 2023 21:37:12 +0200

The template

Title

The title of the strategy (and tactic).

Necessary assumptions

Why is this necessary?

Strategy

What for?

Parallel assumptions

Why is it possible? Why is it difficult?

Tactic

How?

Sufficiency assumptions

Why is sufficient?

Resources

The TOC approach to Strategy and Tactics by Eli Goldratt, Rami Goldratt, Eli Abramov.
What is Strategy & Tactic Trees and how do you build them the TOC way by Dr Alan Barnard.

Goal tree color scheme

Sat, 06 May 2023 09:59:21 +0200

A nice way to use the goal tree is to use a color scheme to show which goals are already fulfilled and which are not. A schema that can be used is red, orange, green.

color	when
Red	The condition is not fulfilled
Orange	The condition is partially fulfilled
Green	The condition is completely and satisfactorily fulfilled

The nice thing about the tree and the color scheme is that when you have colored the leaf nodes, you can then combine the colors upwards. When all child nodes have the same color, use that colors, when it’s a mix you use Orange.

Goal Tree

Sat, 06 May 2023 09:25:14 +0200

A Goal Tree consists of nodes and arrows. The nodes are your goals, critical success factors and necessary conditions. The arrows are the logical connections. These arrows connect goals with the sub goals.

An arrow can be read as “In order to have X, we must have Y”. In a small diagram, this looks like: X ← Y.

You start with the Goal. The Critical Success Factors are necessary to reach your goal. And you have Necessary Conditions that are necessary to reach the Critical Success Factors.

Improve a Goal tree

Sat, 06 May 2023 08:54:37 +0200

To improve a Goal tree, you need to examine the items in the tree. Using a technique similar to five why’s you can improve the goal tree.

Ask the question: why do you need it?

Example: garden shed

Let’s look at the goal of “Garden shed”. Why do I need a garden shed? Because I need to store my garden tools. Why do I need to store my tools? I want to have a clean garden. Why do I need to have a clean garden? To have a safe garden for the children to play.

Tasks and notes

Sun, 16 Apr 2023 21:06:13 +0200

In Jira, an issue is a task and a note at the same time. The issue is a place to focus the information to the point where you can complete some piece of work.

Four obstacles to thinking clearly

Sat, 25 Mar 2023 11:46:00 +0100

These are four obstacles to clear thinking.

Reality is complex

Reality is complex and you need complex solutions to solve problems.

Eli Goldratt defined the Principle of Inherit Simplicity. This means that reality is inheritly simple. Because of this simplicity, conflicts can be resolved using the following steps.

Clarify the conflict
Surface the assumptions
Challenge the wrong assumptions

There is a relation with shadow work. In shadow work you should also keep conflicts in your mind and try to merge them. One way to find ways to solve conflicts is to find assumptions and try to find where your thinking is wrong.

Conflicts

Thu, 23 Mar 2023 12:11:06 +0100

The Theory of Constraints talks a lot about conflicts. Conflicts are what keeps us from becoming better. On part to becoming better at TOC is to know when you are in a conflict. There are certain words that can help you to notice a conflict.

TOC often talks about the large conflicts. These are the conflicts that most people have a problem with. When you dissolve these conflicts you help the most people.

Hugo and Tailwind

Sat, 18 Mar 2023 22:41:00 +0100

This current website is built with Hugo. I wanted to try to build my own theme with Tailwind. With Hugo it is not very easy to use Tailwind. The biggest problem I found was that Hugo does not reload CSS with livereload.

Current Reality Tree

Thu, 29 Dec 2022 13:10:30 +0100

The Current Reality Tree is a sufficiency tree shows (part of) the current situation of a system. It is used to model how causes and effects lead to certain undesirable effects (UDE). The arrows in the tree show which cause leads to which effect.

When there multiple arrows from a cause to an effect, then each cause creates the effect by itself. Removing one of the causes will perhaps lessen the effect, but not remove it completely.

Compatibility of Markdown in Logseq

Wed, 28 Dec 2022 10:00:00 +0000

These are some of my thoughts about Markdown in Logseq. In this note I try to find the assumptions behind the conflict.

This is thinking I did on my and is not associated with how Logseq will work now or in the future, this also does not represent goals of the Logseq team. This is what I think the goals could be.

The conflict

Goal tree

This is the goal tree, for some of the features we “need”.

Logseq show brackets setting creates a conflict

Thu, 15 Dec 2022 14:24:32 +0100

With a setting, a conflict between two options becomes a choice (or compromise) for the user, instead of a situation to be solved by the designer. The conflict itself has not been evaporated.

The checkbox to show or hide brackets in Logseq is an example of this. I use Logseq as an example, because it is the software that I use daily and like a lot.

The conflict

When the setting enabled this improves the editing experience. The brackets are already in the text and so the text doesn’t move as much when you click the text to edit. This fills the need for a better editing experience.

An easy method I learned for first time users to start using Logseq for real

Sat, 10 Dec 2022 21:41:55 +0100

I often see people searching for the perfect structure or method to use a tool like Logseq. You don’t need that. You only need a simple structure and the will and habit to fill daily notes pages. Logseq does not need much structure to become useful. And when you use it more, it becomes even more useful.

The daily note page makes Logseq powerful without the need for much structure. The following example shows a daily note page. I added a few lines to show how it could look.

CRDT Tree Algorithm

Fri, 02 Dec 2022 22:48:22 +0100

I found a piece of code and algorithm that makes it possible to collaborate online on tree structures. I have been using Logseq for the last few months and this algorithm seems to be a way to make collaboration on an outliner possible.

Evan Wallace described this algorithm. The page also includes a demo application. I have rewritten this demo application to Go and implemented a network protocol with mangos. Mangos is a nanomsg port in Go. Mangos can use websockets. This makes it possible to use a Go backend server with nanomsg protocols to send the changes from other clients back and forth between the clients. My implementation is just a prototype.

Switch to Netlify

Sun, 27 Nov 2022 14:12:26 +0100

I started with Digital Ocean apps yesterday to try out a new static website. I found that it is not possible by default to have redirects. So I switched the platform to Netlify. It is possible to add redirects there.

Using Hugo to generate my website

Sat, 26 Nov 2022 22:58:31 +0100

In the beginning my website blog was generated with a Ruby app, that I wrote myself. Later I rewrote that app in Perl. It used the same file structure. Today I converted my files to a Hugo site, by copying the files and adding YAML front matter. With Perl this is really easy. See convert.pl.

The index.yaml contains the title and date of the blog posts. Each $doc contains the name of the source file and the output file. As you can see it was not hard to convert the structures from one to the other.

Year in review: 2019

Fri, 20 Dec 2019 14:00:00 +0100

I was always interested in the Year in Review posts from people. It looks like it is something that you can’t create after the fact. You need to keep some notes, and perhaps log data about the things you did. Some people keep count of the number of emails sent and received or kilometers traveled. After the fact, these kinds of details are rather hard to come by.

To make this a great post, I will have to dig into the notes I made, the data that I collected, and the posts I wrote on the other blog and combine these into witty graphs and paragraphs of enjoyable words.

Ekster: a microsub server

Mon, 31 Dec 2018 16:11:58 +0100

Ekster is a Microsub server. As far as I know Ekster was the second implementation of a Microsub server.

Microsub is a protocol for feed reader applications. Ekster fetches web pages and feeds and gathers the entries into channels. A channel contains multiple feeds, these feeds are combined into a timeline.

Ekster can find entries from pages that are marked up with microformats. It uses the go-microformats library to get the MF2 structure and converts these microformat items to JF2. JF2 is a simplified version of MF2, which is easier to display in a Microsub reader.

A tour of my Indieweb projects

Wed, 15 Aug 2018 16:24:02 +0200

Earlier this year I started to rebuild this website to work better with the Indieweb. At the same I build a new website P83 with Indieweb support from the start.

This website is generated from static files with a system that I created the first time when I started writing in the website. Not much has changed, except that I some point a few years ago I rewrote the whole system in Perl.

Writing a WebSub hub

Wed, 31 Jan 2018 20:58:02 +0100

This week I’ve been writing a WebSub hub. It’s server program that receives subscription and publish requests and sends notications to the subscribers when a website changes. The website itself sends a request when the website changes. This way the subscribers know when to update their feeds.

Implementing the server is quite simple, especially with the help of a website that checks your implementation, websub.rocks.

WebSub Rocks! is a validator to help you test your WebSub implementation. Several kinds of tests are available on the site.

Collection and select

Sat, 27 May 2017 11:48:00 +0200

Sometimes you need to get a lot of information from the database and you need it fast. The way to get this information normally would be to use the Magento collection for the model. It would look like this:

$collection = Mage::getModel('customer/customer')->getCollection()
    ->addNameToSelect()
    ->joinAttribute('billing_city', 'customer/city', 'default_billing', null, 'left');

foreach ($collection as $customer) {
    // Use $customer
}

The problem with this way of getting the information is that it loads all customer information into memory, which can take a long time when you have many customers.

XML-lister

Thu, 31 Mar 2016 21:33:49 +0200

XML lister is a small program that lists the elements, values and attributes of XML files.

<?xml version="1.0"?>
<layout>
    <default>
        <reference name="root">
            <reference name="content">
                <block name="product.info">
                    <action method="test">
                        <param>test</param>
                        <param2>test2</param2>
                    </action>
                </block>
            </reference>
        </reference>
    </default>
</layout>

XML lister will print the following list:

layout
layout/default
layout/default/reference
layout/default/reference@name   root
layout/default/reference/reference
layout/default/reference/reference@name content
layout/default/reference/reference/block
layout/default/reference/reference/block@name   product.info
layout/default/reference/reference/block/action
layout/default/reference/reference/block/action@method  test
layout/default/reference/reference/block/action/param   test
layout/default/reference/reference/block/action
layout/default/reference/reference/block/action/param2  test2
layout/default/reference/reference/block/action
layout/default/reference/reference/block
layout/default/reference/reference
layout/default/reference
layout/default
layout

A few days ago I wanted to find out if there are places in Magento layout XML files where reference elements are used inside other reference elements. With XML lister it becomes really easy to find places like this.

Rewrite XML with xmlstarlet

Wed, 16 Mar 2016 14:23:32 +0100

XML Starlet is a program that makes transforming XML documents really simple.

The command that you need to transform an XML document is the following.

xmlstarlet tr [<options>] <xsl-file> {-p|-s <name>=<value>} [ <xml-file-or-uri> ... ]

The XSL file that transforms a document to itself is this. It copies all elements, attributes and texts. We can extend this file to remove, add, or transform elements.

<?xml version="1.0" ?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <!-- IdentityTransform -->
    <xsl:template match="/ | @* | node()">
        <xsl:copy>
            <xsl:apply-templates select="@* | node()" />
        </xsl:copy>
    </xsl:template>
</xsl:stylesheet>

To remove an element, we match an element and don’t call apply-elements inside it. This example will remove the remove me element.

Removed Analytics

Thu, 06 Nov 2014 15:02:08 +0100

I just removed Analytics from my website. It’s not important for me. I don’t have the time to look at it.

Sorting DNS records

Thu, 04 Sep 2014 10:33:44 +0200

I don’t update my DNS records often, but when I do I like these records sorted.

A DNS record consists of the following fields: domain name, type and prio (for some types). I use these fields to determine the order of the records. That is also the order in which these fields should be ordered.

The first insight I had about sorting domains was that the domain names consist of parts separated by a period. The domain names may be strings. But a domain name is actually a reversed array of strings. We map the domain name from “sub.example.com” to [ “com”, “example”, “sub” ]. This puts it in an order that makes lexicographical compare work. To compare domain names is to compare these arrays of parts with a lexicographical compare function.

Rotate one to the left

Mon, 18 Aug 2014 11:37:49 +0200

Last week I wrote a small function in Perl that rotates and array to left.

The function takes the item from the front and appends it to the back.

# precondition: @list >= 1;
sub rotate_left_by_one {
    my $ar = shift;
    my $item = shift @$ar;
    push @$ar, $item;
    return;
}

After calling this function as many times as the length of the array, it leaves the items in the same order they started in. Every call to this function puts a different item in the first location. I use it to compare this item to the rest of the items.

Low level code

Fri, 23 May 2014 11:54:55 +0200

Google released the PDF code of Chrome just a few days. I took a look at it. This file (core/src/fpdfdoc/doc_vt.cpp) is an example of how the code looks.

Sometime later it dawned on me that this code is built out of only low level pieces. There are almost no algorithms extracted to functions.

An example would binary search. There are five copies of binary search hidden in just that file. No wonder this file is 1864 lines of code.

StrictWeakOrdering

Tue, 13 May 2014 22:32:12 +0200

I always forget what strict weak ordering means, but it’s quite simple, actually.

My explanation is based on the Programming Conversation of last week and I hope this will help me remember the next time I hear about this.

Let’s start with ordering. A relation is an ordering if it is transitive.

ordering -->  for all a, b, c: r(a, b) and r(b, c) => r(a, c)

And now strict.

Broken interface of Math.min

Tue, 29 Apr 2014 12:18:29 +0200

In an article about creating a column layout I found the following two lines of code:

var min = Array.min(blocks);
var index = $.inArray(min, blocks);

This first finds the minimum value in blocks and then the index of that value. This combination of lines is very strange. Array.min already knows the index of the minimum element and throws it away. Then the programmer needs to find the index again with a linear search.

Stability in column layout

Tue, 29 Apr 2014 11:18:44 +0200

I was reading the notes on programming PDF and found a discussion about writing min and max functions for multiple arguments. I didn’t what to use this for. Also there was a discussion about stability. Stability is when you leave elements in the same position when they’re the same. This seems to be about sorting.

At the same I was implementing a Pinterest like column layout. I already had a working version. But sometimes the images weren’t loaded completely and the algorithm would overlap images, because the height of the element wasn’t known.

Renewed interest in C++

Tue, 22 Apr 2014 14:41:37 +0200

In the previous post I showed a playlist of presentations by Alexander Stepanov, the creator of STL. In these videos he talks about algorithms and data structures (written in C++). This principled explanation of programming makes a lot of sense to me. And has me take a renewed look at C++.

Programming conversations

Sun, 06 Apr 2014 12:31:46 +0200

BitTorrent Sync

Sun, 29 Dec 2013 14:19:11 +0100

A month ago I wrote about File Transfer for mobile phones. There I wrote how I think a solution for file transfer should work. A few days later I found Bittorrent Sync. Problem solved!

Use ZeroMQ to control a receipt printer

Wed, 20 Nov 2013 14:48:44 +0100

A customer needed a solution to the following problem. There are multiple web POS systems that need to print to a receipt printer. The web server is not in the same place as the POS terminals, but they are connected to a network.

To solve the problem I used ZeroMQ to connect the web server to the receipt printers. The current solution consists of four parts.

Web app
Web server (connects a PUSH socket to a PULL socket)
ZeroMQ device (a multiplexer receives from a PULL socket and sends these to a PUB socket)
Computer with receipt printer (a sink that receives on a SUB socket subscribed to its own address)

First a user in a browser clicks the button to print a receipt.

File transfers for mobile phones

Sun, 17 Nov 2013 17:13:02 +0100

Sometimes I need to copy a file from my computer to my phone. That’s should be really easy. But it’s not. I would like it to work like this:

I put a file in a folder.
If my phone is on the same network, the file should be copied from the computer to my phone, without further actions from me.

And that’s it. The file shouldn’t be copied to a server somewhere else. It should only move from my computer to my phone and never touch the internet.

Redis queue design choices

Fri, 06 Sep 2013 11:25:09 +0200

In a previous post I wrote about simple job queue in Redis. In this post I like to write a bit about the design choices. I think these choices illustrate a point about design.

Job handle

The job handle in the code is create by the client (with help from the Redis server). This job handle is passed to the queue in Redis and picked up on the other side by the worker.

I rewrote my blog software in Perl

Mon, 02 Sep 2013 14:29:47 +0200

In the last few weeks I have rewritten my blog software in Perl. The old version used Ruby. I wrote that version, because I wanted to try out Ruby. The software is about as old as the blog itself.

The new software is written Perl. I use many new modules in Perl. For example Moo, Path::Tiny and Carton.

Moo is an OO library for Perl. It allows me to write OO code in Perl without any boilerplate. One of the nice features of Moo is the lazy setting for the is attribute. This makes the attribute lazy and calls a builder when initializing it.

Simple queue in Redis with Perl

Mon, 02 Sep 2013 13:59:46 +0200

Sometimes you need to have a asynchronous worker written in Perl. The small script here takes a job from the queue and executes the code. It only takes a few lines of Perl.

use Redis;
my $redis = Redis->new(encoding => undef);

my $queue_name = 'q';
my $timeout    = 10;

for (;;) {
    my ($queue, $job_id) = $redis->blpop(join(':', $queue_name, 'queue'), $timeout);
    if ($job_id) {

        my %data = $redis->hgetall($job_id);

        # do something with data...
        # ...

        # remove data for job
        $redis->del($job_id);
    }
}

The client would look like this:

Dockerfile for Pinto server

Wed, 24 Jul 2013 14:08:43 +0200

Yesterday I created Pinto server on a server with Debian. Today I did the same but with Docker. Docker is way to run processes in their own sandbox. Docker uses a Dockerfile to create an image that run a certain process. The Dockerfile that I used to run pintod looks like this:

FROM ubuntu
RUN apt-get -y install curl perl build-essential
RUN curl -L http://getpinto.stratopan.com | bash
RUN mkdir /var/pinto
VOLUME /var/pinto
EXPOSE 3111
RUN adduser --system --home /opt/local/pinto --shell /bin/false --disabled-login --group pinto
ENV PINTO_HOME /opt/local/pinto
ENV PINTO_REPOSITORY_ROOT /var/pinto
RUN /opt/local/pinto/bin/pinto init
CMD /opt/local/pinto/bin/pintod

I created a volume for /var/pinto that contains the repository. The pinto init doesn’t initialize it, it seems. If I later mount the volume in on the host, the directory is empty, because the host directory was empty.

Dist Milla and Pinto

Tue, 23 Jul 2013 21:25:21 +0200

Today I was working on a private module that I use to write web applications. A few weeks ago I found out about Milla. Milla is a plugin bundle for Dist::Zilla, which makes it easy to create Perl modules.

When you’re ready Milla automatically releases your new module to PAUSE. This is really useful for public modules, but not that useful for private modules.

Pinto is like CPAN in a way. It’s really easy to create a private CPAN with it. That’s what I did today. It contains the pintod script that starts a webserver, which is compatible with the CPAN infrastructure. It allows you to install modules from it with cpanm.

Create your own YouTube playlists

Sun, 09 Jun 2013 14:40:51 +0200

A few days ago Mindcrack Ultra Hardcore season 11 started. In Ultra Hardcore the play by special rules, that are different from vanilla Minecraft. The biggest difference is that players don’t regenerate health automatically. They need to eat golden apples to increaes their health. These apples are harder to make, because you need golden ingots instead of golden nuggets.

Each season players record videos of their perspective of the match and post these videos to their YouTube channel. This season these videos are posted every other day around 22:00 UTC. This is mostly to give viewers the opportunity to watch multiple perspectives. The total running time for the first episode was about 7 hours. That’s a lot of video to watch.

Load Firefox search in background tab

Mon, 06 May 2013 13:53:48 +0200

Today I noticed something that bothered me. When I search in Firefox through the right-click context menu the search results open in a new tab and Firefox switches automatically to the new page. I remembered there is option that makes Firefox open new links in the background and I thought that maybe this option was disabled. The option was enabled as it should be.

I opened a few links and it behaved as expected. The search results however still opened in a new tab in the foreground. This was unexpected. For me it seems that links and searches should open in a new tab in the background.

A universal subscribe button

Mon, 22 Apr 2013 17:24:31 +0200

SubToMe is a universal subscribe button that you can add to your weblog. You just add small bit of HTML that shows a subscribe button. The software is written in Javascript and runs in your browser. It doesn’t need a central server. Take a look and add it to your weblog.

Changes to the heredoc parser example

Mon, 22 Apr 2013 16:31:32 +0200

Jeffrey Kegler, the author of Marpa, was kind enough to suggest a few changes to the parser from the previous blog post.

Two of the three regular expressions were replaced with calls to the Marpa recognizer. The first one was replaced with a call to the pause_span method, which returns the start and length of the lexeme that caused the pause. Passing these two values to the literal method which returns the substring from the input string. This removes the need to mess around with the pos() from the input string.

Parse a heredoc with Marpa

Fri, 19 Apr 2013 18:13:01 +0200

I already wrote that I’m quite interested in the things Marpa can do for writing parsers. The latest release of Marpa includes an addition that makes parsing strange languages even more possible. The new functionality allows you to control the parser from your own code while it doesn’t stop you from using the internal scanner.

To try out this new functionality in Marpa I tried to write a parser for a small language with just one function and heredocs. I choose this language, because it can’t be parsed with just the internal scanner. The scanner needs to find the end marker with the same name as the begin marker of the heredoc. The parser doesn’t know about the name of the marker, just that it looks like a marker.

Apps that share

Mon, 08 Apr 2013 12:27:20 +0200

On my phone I can share stuff between apps. It’s like pipes. I write something in one app and send it to another app that posts it to my weblog. The apps in question are Draft and WordPress. It shows how easy it is to send stuff between apps. The apps don’t even have to know the other app exist. Why is this easier on my phone than on my PC?

Grok

Mon, 11 Mar 2013 13:02:00 +0100

In this video Steve Yegge talks about a project he’s working on called Grok. I seems ambitious and useful.

I worked on a few parsers in the last few months and it seems that most of the work still has to be done even if you’ve got a parse tree of a language.

Yegge explains that they don’t write the parsers themselves, but use the work compiler builders have done. This is a good idea, because writing a parser isn’t easy, even if you have a really good tools to build a parser with.

DIY refactoring

Tue, 29 Jan 2013 21:52:15 +0100

Yesterday I released a piece of code the includes a parser, a rewriter and serializer for a small expression language.

The code is an example how you can parse source code and build a tree, rewrite the tree using two expressions and serialize the tree back to a piece of ‘code’.

The idea that I used here was to improve the language by adding a way to specify structural variables. The variables start with a colon :, but are otherwise like variables.

Generate a list of the same thing

Sun, 20 Jan 2013 12:12:28 +0100

Last year I wrote about how we can build an extended syntax for Marpa on top of the basic interface.

For the counted rule lhs ::= rhs{5} where you want to match the right hand side multiple times, we can just generate the rhs item 5 times.

This isn’t the right thing. Jeffrey pointed out that you can build these {min,max} rules up out of blocks.

Then I remembered a piece of code from Elements of Programming which explained that it’s possible to generate the Fibonacci series in O(log n) time. The same should be possible for the counted rules.

What you could blog about

Thu, 03 Jan 2013 15:55:47 +0100

I guess the best way to think of a blog for me is that you can relate what you did and maybe talk about why you did that.

I wish everyone in the world would blog by Chris Coyier lists five nice things you could blog about.

When your reading a blog you can get a little bit of perspective on their life and their world.

Can't write directly

Thu, 03 Jan 2013 10:24:32 +0100

Tom Morris wrote some time ago about Posting UIs on the Indie Web:

The type of writing we do is influenced by the tools we have, and by the experience of the services we use.

I write my posts in Vim with a small script around it that adds the content to the blog post index. Then I generate the static files and publish (with rsync) everything to the server.

Focus on a simple product and protocols

Wed, 02 Jan 2013 21:26:47 +0100

I’d like to propose here that it’s a good idea to start with a simple piece of software with explicit simple protocols that make it a good place to start.

Others will be able to build a similar product that uses the same protocol. And still others will be able to connect to the other end of the protocol to use it in their software. Every piece of software created like this can be replaced with better software or new ideas can be tried without recreating everything from the ground up.

One thing well

Wed, 02 Jan 2013 17:03:40 +0100

What would a web application that does one thing well look like? What would it need to be able to do?

Let’s say you want to make a social network application. Whatever that means. What would the use cases be? Just so you know I’m not trying to be complete here.

User creates an account
User logs in to his account
User writes a short post
User reads a post written by another user
User updates his profile
User looks at a profile
User looks at a list of private messages
User writes a private message to another user
User reads a private message from another user
User replies to a private message
User adds a friend to his friend list
User removes a friend from his friend list
User likes a post / photo / comment / link
User uploads a photo
User comments on a post from another user

Each of these use cases should be a small service. For some two or more use cases could be combined, because they’re complementary. Currently every service needs to write a new version of these use cases.

Simple and impossible

Wed, 02 Jan 2013 16:42:53 +0100

Build simple programs that work together.

Build software that does one thing well.

Have you heard that before?

If this is such a good thing, why don’t we do that?

Because it’s impossible. Software needs to do many things to the one thing.

We wouldn’t even know what one thing would look like.

Rivers and massive blogposts

Mon, 24 Dec 2012 19:57:37 +0100

I build a program called Pompiedom. I host a test river about Perl. It shows feeds from all sources in one page. Just like (rss) planets.

One of the problems is that there are a lot of different types of feeds. There is no default way that people create feeds and no feed has the same kind of content. I think this is a good thing.

The problem I have currently is that some feeds contain massive blog posts. These massive are really nice to read and they are really hard to show well. Especially when mixed with short and small link blog posts.

Anti-Fragility again

Sat, 01 Dec 2012 16:10:34 +0100

Two years ago I first asked the question:

How can [anti-fragility] be used in software and other computer systems?

The answer was (almost) right in front of me.

Kent Beck shows how to use small safe steps to write and change software.

Alexander Stepanov writes in notes.pdf pg. 111 how we get mathematical theories in programming:

While it is possible to keep providing more and more definitions, it is not the correct approach to building a theory. We often get the idea that a mathematical theory is built in a logical way starting from definitions and axioms. This is not the case. The definitions and axioms appear at the very end of the development of a good theory. It invariably starts with simple facts that later on are generalized into theorems, and only at the very end the formal definitions and axioms are developed. Sadly enough, many people who try to apply mathematics to programming start with axioms and then end up criticizing the real programs for not corresponding to their “beautiful” axioms. To build a theory of data structures we need to start with simple algorithms operating on data structures and only when we have looked at many specific algorithms can we come up with satisfactory theories.

The different parts of a template

Wed, 21 Nov 2012 22:07:20 +0100

I have been thinking on and off about how to make Marpa parse a template language. I tried many different ways to create a tokenizer for this parser, but until this week I couldn’t get something reliable. The week I started with the tokenizer from the example code from Jeffrey Kegler’s blog post about how to develop a parser iteratively. This got me on the right track to create my parser. Let’s start with ‘specifying’ the language.

Take notes and focus

Fri, 07 Sep 2012 16:18:22 +0200

I use a small list to remind me of opportunities where I can improve my software. When I find an element that I can improve, I write down a reminder so I know where to look. Because I write these reminders I can focus on the task at hand. I take care of the other problems another time. When I’ve completed an item on the list I strike it through and start work on the next one.

Small safe steps

Sat, 25 Aug 2012 16:42:59 +0200

I really like the notion Safe steps in Responsive Design:

Safe Steps. Resolve the tension between efficiency and safety in favor of safety, then learn to take small, safe steps fast enough that from the outside it looks like you are flying.

I want to show an example of a change that changes the interface, without the need to change the callers. In the end I want to remove the call to get_controller_class. But first I make a small safe step. I have a method like this (in Perl).

Instantiate an algorithm

Sat, 14 Jul 2012 13:55:44 +0200

I wrote an internal API for products. The API consists of many methods that make changes to the database. The value is in the database is the original value and the code changes it.

For every different change there is a method that makes this change. The API uses the database as internal memory.

Every method in the API gets data, updates it or writes it. There is no code that makes changes to the product in the memory. Let’s start with a simple example.

Fibonacci for web developers

Thu, 12 Jul 2012 12:43:00 +0200

We start by creating a database table. This is very important for web applications, because web applications can’t store state in memory, like desktop applications.

CREATE TABLE `fib` (
    `n`    INT  NOT NULL,
    `fib`  INT  NOT NULL,
    PRIMARY KEY (`n`)
);

Now we write the PHP code. You can write the HTML form yourself, it’s not that hard.

Do you write code like this? I know I do.

App store for cloud hosting

Thu, 05 Jul 2012 14:11:00 +0200

In my last post I wrote about what will come after PHP. In a way PHP is the only language you can use if you want your software to be used on a variety of platforms. Software written in PHP is easily hosted and configured on shared hosting, a dedicated server or on your own PC.

PHP as a language is pretty bad. No more articles have to be written on that subject. However, PHP as a hosting platform is everywhere. Much succesful open-source web software is written in PHP. Mediawiki, Wordpress and PHPMyAdmin are just a few of the big ones, that I use almost every day. This is software you can just host yourself.

What comes after PHP?

Fri, 29 Jun 2012 16:16:24 +0200

In the The PHP Singularity Jeff Atwood writes about how PHP is the only option for server code that runs everywhere. And that if you don’t want to write PHP, you have a problem, because there aren’t any other options.

This is not an abstract, academic concern to me. I’m starting a new open source web project with the goal of making the code as freely and easily runnable to the world as possible. Despite the serious problems with PHP, I was forced to consider it. If you want to produce free-as-in-whatever code that runs on virtually every server in the world with zero friction or configuration hassles, PHP is damn near your only option. If that doesn’t scare you, then check your pulse, because you might be dead.

Audio articles

Sun, 27 May 2012 14:04:20 +0200

Many podcasts I listen to, are around one hour and two and a half hours. This is pretty long, but most of the time worthwhile to listen to. I have a commute of an half hour each day, and some time to listen to somethings. But a two and a half hour show, will take 5 commutes to hear it all.

Are there any podcasts that are between 10 and 15 minutes long and are focused around one idea or news item?

They wouldn't install if not for packages

Mon, 21 May 2012 10:38:50 +0200

In Use of DBI in Sqitch, Wheeler writes about Sqitch, an application for SQL change management.

Sqitch uses the native database client applications (psql, sqlite3, mysql, etc.). […] The IPC is a huge PITA. Furthermore, getting things properly quoted is also pretty annoying

I would expect this when you use SQL command-line tools in other tools. Of course, this is Perl, which is better at this kind of thing than other languages.

Great tool: sshfs

Sat, 19 May 2012 18:24:10 +0200

Do you use servers on the internet? Do you connect to them with ssh? Then you should take a look at SSHFS.

It allows you to mount a directory on a different computer as if it’s a directory on your own. And then sshfs takes care making sure that your commands do the right thing. It’s amazing.

In The Hideous Name Pike and Weinberger write about a similar thing. You can profit if you can the same tools in the same way regardless if you’re on your local machine or on a remote machine.

Simple rules parser for Marpa

Sat, 14 Apr 2012 12:04:54 +0200

I had a nice idea a few days ago. A simple module that creates the rules part of a Marpa grammar, but without code generation and lexers. Just the bit that Marpa::XS::Grammar uses.

So I wrote it in a few minutes. It’s not really complicated and provides an example how to write a short parser.

Lets start with a short example of what you would write.

use Marpa::XS;
use MarpaX::Simple::Rules 'parse_rules';


my $rules = parse_rules(<<"RULES");
RULES

my $grammar = Marpa::XS::Grammar->new({
    rules => $rules,
    ...
});

At the ... you should add more arguments to Marpa::XS depending on how you want to use it. Now let’s write a simple example of some rules.

The three parts of the next web

Sat, 07 Apr 2012 15:56:24 +0200

The three problems that need to be fixed are subscription, feed reading and feed creation.

Subscription

Subscribing to feeds is really hard. It should be really simple. Unsubscribing should be just as simple.

See something that you want to subscribe to? Click the subscribe button.
Done!

Unsubscribing should be just as easy.

You see a post in your feed reader that you don’t want to see.
Click Hide.
Show an option for unsubscription.
Click, gone!

Or:

What's allowed in the basic Marpa grammar

Thu, 05 Apr 2012 23:10:01 +0200

In my last post I wrote about what the different rewrites of more advanced rules would look like. The question now is, when do you have a grammar that’s basic enough?

This is the basic configuration of the Marpa::XS class. In this configuration you can specify left hand sides and right hand sides and the star and plus operator. If your tree looks like this, then it’s basic enough.

Parser    ::= Rule+
Rule      ::= Lhs DeclareOp Rhs
Lhs       ::= Name
Rhs       ::= Names
Rhs       ::= Name Star
Rhs       ::= Name Plus
Names     ::= Name+

This grammar consists of only 7 lines, so that’s pretty good. This are the basics, but it assumes a few things.

Rewriting Marpa rules

Wed, 04 Apr 2012 23:15:47 +0200

Let’s try to write some rewrite rules for a next level Marpa to a lower level Marpa. The syntax is not important, this is about how we can rewrite the rules.

In the actual grammars none of the left side patterns work, but all of the right side rewritten version should work.

Alternations

An alternation is a rule that can match either way B, C or D.

A ::= B | C     =>  A ::= B
                    A ::= C

A ::= B | C | D =>  A ::= B
                    A ::= C
                    A ::= D

Plus, Star

Plus means match one or more times, star means match zero of more times. Normally you can’t use + or * inside of a rule. Only whole rules can be used like this. If you want to use these you need to create a new rule and use it inside.

Prodromou's Law of Internetworks

Fri, 30 Mar 2012 15:06:52 +0200

No network joins an internetwork smaller than itself.

source

OExchange for subscribing to feeds

Mon, 26 Mar 2012 10:02:09 +0200

Yesterday I was working on my realtime feed reader (and writer). I can read feeds with this, but I can also write posts. With it you can write a small post with a title, description and link.

When I was looking around for websites that support WebFinger I found a similar thing on Twitter. It contained the host-meta file, but instead of showing WebFinger related links, it showed something called an OExchange link. So I took a look what it was.

Building a parser with Marpa::XS

Wed, 14 Mar 2012 22:42:13 +0100

Tonight I wrote this parser in Perl with Marpa::XS. The nice thing about Marpa is that it will tell you which terminals (or tokens) it expects at the current position. So instead of guessing what the next token will be you can just try to parse a token and try it.

I got the general idea from the TAP::Spec::Parser. The difference is that it will try all alternatives at once, while mine tries each after the other until one works.

Implicit algorithms in templates

Mon, 05 Mar 2012 22:53:26 +0100

I was thinking about implicit algorithms and implicit datastructures and thought how this applied to templates in web applications. I found that there are a few places where I write the same template code with just a few different pieces.

One of the examples is a piece of code for showing a text field with a few labels around it. This piece of template code is used for almost every field in the product edit (and new) form. This is repeated code, but we should not do this, right?

Implicit algorithm in a small game

Mon, 05 Mar 2012 21:47:16 +0100

I was working on a small game that displays some blocks. These blocks need to move. The way to make these blocks move is by changing the x and y position over time.

The way I did this in the game was by calling a tick() method every 1/60th of a second on every block that could be moving. Then the block can change it’s position according to some algorithm. I just wrote code that makes these changes to the position.

Publishing if it's not ready

Mon, 05 Mar 2012 21:45:09 +0100

I have an article in the pipeline about implicit algorithms (and datastructures), which is a continuation of a few articles I wrote last year and the year before. It explains the same idea, but from another point of view: a small game that I started to write.

The thing is that the article isn’t that good. Especially the example is too simple. Now it just hangs there. It doesn’t move and I don’t want to touch it anymore.

Start blogging

Thu, 23 Feb 2012 21:22:54 +0100

Jason Cohen wrote a nice article about starting with blogging. One of the ideas he has about this is that you start with an article written by someone else that you like. Then you quote it and elaborate or reply to it.

This is a nice way to start blogging. The thing that often happens to me is the following. I follow this idea, but when I start writing I move so far from the original point of the article that it doesn’t even matter anymore to the new blog post. Then I remove the quote from the top and have a whole new article. I still like to link to the article, but it just doesn’t make any sense anymore.

Best feature ever

Mon, 30 Jan 2012 20:17:49 +0100

Don’t you just hate it when you click a link while you’re on YouTube watching a video. Before you realize what happened you click the back button. Normally this will reload the page and start the video from the beginning.

But not today. It continued at the same point where I left. That’s how it should be.

Added rssCloud to my weblog feed

Fri, 20 Jan 2012 12:59:02 +0100

This is my first post with rssCloud enabled. It’s not that hard, if you’ve have created the infrastructure already. The infrastructure can be found on github: github/pompiedom-rsscloud and github/pompiedom-ping.

Poking from the sideline

Fri, 13 Jan 2012 12:30:13 +0100

I really love the thoughtful blog posts and videos from people who are in the middle of the thing they’re talking about. Those people know what they are talking about and also have a way to make a change for the better.

Christopher Hitchens was a author and journalist and fighter against religion and absolute morality. His articles in Vanity Fair are both eloquent and interesting. Also see him speaking against dictatorships and totalitarian regimes of all kinds.

Running Facebook costs a lot of money

Mon, 26 Dec 2011 08:51:32 +0100

Advertising on Facebook:

It now costs over a billion dollars a year to run Facebook, and delivering ads is how Facebook pays for this.

It’s amazing how much money it costs to run some PHP doodads and spying for free.

Via: Daring Fireball.

Keystoning

Thu, 22 Dec 2011 17:08:19 +0100

In this presentation Kent Beck talks among other things, about a development technique called Keystoning. Someone from the audience asks him what it is. I didn’t know it either and that means someone else probably also doesn’t know. It’s really useful for bigger features and I have used it many times without even knowing it.

What is keystoning? Change the user-visible parts last. This way the changes seem to have come really fast for the user. You can change a lot of code, without making a change to the user inferface.

X is dying

Thu, 08 Dec 2011 14:36:23 +0100

Things that aren’t alive, can’t die. So if you write an article with the title “X is dying”, you should make sure that X was alive in the first place. If it wasn’t alive, you should try and be more specific about what you mean.

Possible meanings

People used X in the past, but don’t anymore.
Some people still use X, but will stop in the future.
People use X, but don’t know what X is.
People use X, but you don’t like it.
People use X, but you don’t want them to.
I don’t use X.
I know someone who doesn’t use X.
I’m a sad and miserable person, just hating about things. Oh, and people use X.

And every time I used people above you replace it with customers, users, developers, companies, grandma’s, moms, dads, your neighbours, or your pet.

Taking back "I don't know"

Mon, 05 Dec 2011 21:32:48 +0100

In I Don’t Understand What Anyone Is Saying Anymore Dan Pallotta wrote about business-speak:

It involves the use of words such as “space,” “around,” “synergy,” and “value-add” with a healthy dose of equivocators like “sort of” and “kind of” to ensure that there is no commitment to anything being said…

Perhaps a solution can be found in a simple little sentence that gives us some room to think. “I don’t know.”

From idea to weblog to research

Fri, 02 Dec 2011 14:11:47 +0100

While I was doing my morning reading I came across this weblog by Jeffrey Kegler about his parser called Marpa. My post is not about his parser, even though it’s very interesting. This post is about the way the weblog guides and explains the work and ideas in the parser. It even includes historical information about where the ideas come from.

It made me think about the work Simon Peyton-Jones has done on writing a research paper. He explains that writing a paper helps your thinking. On the fifth slide he says that instead of first doing research you start with an idea (any idea) and then write a paper. In the course of writing this paper you will do the research needed to fill in the blanks.

Attribution

Fri, 02 Dec 2011 13:05:23 +0100

Sometimes a story just gets an idea going. This time it was about linking and attribution in articles on the web. On Daring Fireball, there is a good example pointing to a bad example.

I don’t understand why there aren’t more links to weblogs and other places in the newspapers. I could guess, but I won’t.

Writing an essay

Sat, 26 Nov 2011 14:49:08 +0100

In The Age of the Essay Paul Graham wrote:

When I run into difficulties, I find I conclude with a few vague questions and then drift off to get a cup of tea.

Seems just like the thing I did in my previous article. With the difference that I got a cup of coffee.

Put the obviousness into code

Sat, 26 Nov 2011 12:29:14 +0100

Let’s get back to what I wrote a few days ago about where you can start. I gave an example about the search engine. I like to look at writing a weblog now.

There exists much software for weblogs. There are hosted versions and there are version that you can host yourself. And version that you can buy. There are even companies where you get a weblog as part of another website.

Obsession x Voice

Thu, 24 Nov 2011 22:01:11 +0100

It’s already a few years ago, that Merlin Mann and John Gruber talked about the concept “Obsession x Voice”.

The thing is that you have to know what you’re obsessed with. That’s hard. You could be really sad to not know what your obsession is. Not knowing is not the biggest problem however. Deep down I know I have an obsession that I would write about. I have written about it. Quite a lot, actually.

Marpa parser for parsing marpa

Sat, 19 Nov 2011 16:16:05 +0100

I just wrote a small program to parse and generate a parser that parses Marpa. Marpa itself doesn’t include such a program for good reasons I assume. Or if it exists I couldn’t find it.

But as this is a small program it only generates a part of the parser. It is also not bootstrapping.

The repository contains a small tokenizer written in Perl. It tokenizes a line of text and passes this on to the token recognizer, which in turn calls the grammer.

I don't like non-working things

Thu, 17 Nov 2011 23:50:23 +0100

I hate to create objects that try to look like other objects. Especially if these objects don’t work like their real counterparts.

Lifeless objects that look like they could work, but don’t.

I also don’t like fake light sabers.

A person only needs so many objects whose only function is the effect gravity has on them.

Where can you start?

Wed, 16 Nov 2011 16:57:06 +0100

In my last post about the base technology I wrote that we need ways to starter higher in the chain of existing software. The place where you can start building your new software is a place between the minimum technology needed and the maximum technology possible.

These two points don’t have to lie on the same line. An example could be a new web search engine. In this example the minimum point is a C compiler and a Linux server.

What's the base technology

Wed, 16 Nov 2011 16:11:16 +0100

As people who make things, we like to start new projects or create new software or websites. One of the first questions that we need to face is what technology will I use? What is the technology that I can build my new idea on top of? And what technology is the easiest to use?

For different projects the answer to these questions is different. And the question is also different for different people.

I deactivated my Facebook account

Sun, 13 Nov 2011 15:25:45 +0100

For people who miss my on Facebook, I’m here and I’m ok. If you want to reach me there are many ways to do that. For example by sending me an e-mail.

You can send me an email at peter@tweevijftig.nl. In the meantime I’m also available on Twitter. But I’m not sure how long this will last.

My web presence as always is here, which it has been ever since 2004 and it will continue to be so in the future.

Must see talk by Alan Kay

Sat, 12 Nov 2011 12:05:40 +0100

Programming and Scaling talk by Alan Kay.

META II

Sat, 15 Oct 2011 23:08:53 +0200

Today I implemented the META II compiler compiler using this paper: META II: A syntax-oriented compiler writing language. The code can be found on GitHub.

An interesting idea from this paper is that the language is really easy to implement using just a few lines of code. The C code is quite a bit larger, but could be made smaller. A bigger problem with the code is that the compiler generates an assembly language program that still needs an assembler and a virtual machine. These two parts need to be created before I can actually test the program.

No future for flash

Sat, 17 Sep 2011 13:09:32 +0200

Now that the future Windows won’t include support for plugins, it’s time to think to change your website and remove Flash.

Writing Plack middleware

Thu, 15 Sep 2011 13:19:32 +0200

Let’s start with this: have you looked at Plack yet? If you haven’t you should. It’s the future of Perl web programming. It’s by far the easiest way to create web software. And the best way to start is to use one of the frameworks that were created already.

One of the nice features of frameworks based on Plack is that it’s really easy to enable kick-ass middleware by just adding one line in the configuration. The other thing is you don’t have to write many of these yourself, they’re available on CPAN.

Pretty colors for charts using Chart

Thu, 25 Aug 2011 16:32:42 +0200

Monday I was creating a graph for my webshop software. I use the Chart module, but the colors and the graph of the default settings aren’t really pretty. So I tried to create a better looking chart. I think I succeeded at least a bit.

Here is the code that I used to get this result:

my $c = Chart::Composite->new(1024, 250);

$c->set(composite_info => [
    [ 'Lines', [1] ],
    [ 'Points', [2] ],
]);
$c->set(precision    => 0);
$c->set(skip_x_ticks => 7);
$c->set(max_y_ticks  => 11);
$c->set(min_y_ticks  => 2);

$c->set(legend => 'none');
$c->set(grey_background => 'false');
$c->set(y_grid_lines => 'true');

$c->set(colors => {
    'background' => [255,255,255],
    'misc' => [200,200,200],
    'x_grid_lines' => [220,220,220],
    'y_grid_lines' => [220,220,220],
    'dataset0'=>[150,180,250],
    'dataset1'=>[120,140,240],
});


my $label = 'x';
my $val   = 10;
$c->add_pt($label, $val, $val);

You should call add_pt for each point you want to show. I use $val twice because there are two graphs that both need the same value.

Hotmail Sweep

Mon, 22 Aug 2011 10:27:49 +0200

Hotmail Sweep is a really powerful idea. It’s an easier way to create email filters, without calling it that.

You can only use two action: move and delete. These are most important ones however. And you can only the from address to filter messages.

Hotmail removed a few options and made the feature as a whole more useful. They could make to easier to create a new folder, that’s still a bit of work.

Moving...

Thu, 18 Aug 2011 16:32:13 +0200

I have moved. It’s been a long time coming, but in the last few weeks I have moved. Not everything is ready yet here, but at least I can write blog posts again on my own computer. I still need to finish the desk, so at the moment I use the dining table.

I like Google Plus

Sun, 14 Aug 2011 13:32:29 +0200

I just need some more people to talk to. So invite yourself using this link: Google+ invites.

Just leave me a message somewhere if you got one.

Your podcast is too long

Mon, 20 Jun 2011 20:12:40 +0200

The last few weeks I heard a few times that people think that some podcasts are too long. I think it the next thing that should happen is that the creators of these podcasts should ask those people the following question.

Why do you think that this podcast is too long?

I don’t think that the length of the podcast is the problem these people are complaining about.

I think that there is a difference between the people asking about the length and listening to the podcast, and the people creating the podcasts. This difference is that the first group has a job that needs them to commute, while the other group stays at home. So the problem is that the podcast is longer than the length of the commute, which makes listening to the whole podcast more difficult.

One

Wed, 20 Apr 2011 17:34:21 +0200

In the article about why we don’t use more data structures in web applications I showed an example of PHP code. I copied the code below. The example shows how we start to write web applications. I will rewrite the code so it says one thing: insert a person into the database.

<?php
    $name    = $_POST['name'];
    $address = $_POST['street'];
    $city    = $_POST['city'];
    db_person_insert($db, $name, $address, $city);
?>

Two things happen in this example. First we get the variables from the $_POST variable. And then we insert the values into the database. First I’ll add the ‘code’ of the db_person_insert function as well.

Moving tweeting of Twitter

Wed, 20 Apr 2011 10:44:00 +0200

Doc Searls says in Let’s move tweeting off Twitter that most online communication isn’t owned by one company:

Blogging, emailing and messaging aren’t owned by anybody. Tweeting is owned by Twitter. That’s a problem.

It is one of the points I tried to make a few days ago. I don’t think we have to move away from Twitter. But I do think we need to at least make it possible for every company (and person) to have their own microblogging instance. And all these instances should be able work together.

Web applications and data structures

Wed, 20 Apr 2011 00:05:39 +0200

There is this question that keeps coming back when I see the code of web applications. It keeps coming back, probably because it relates to the basics of our field.

Why do we forget we learned about data structures, the moment we start to write web applications?

The question points at three things. Why do we forget about data structures? Why don’t we write better code for web applications? The last point is a passive-aggressive jab at all web developers. And I’m one of them.

Decentralization as advantage for companies

Sat, 16 Apr 2011 21:27:37 +0200

Decentralized services, like email, have a big advantage for users. I can send email to anyone that I have the email address of. The advantage for me is that even if my friends use a different email provider, I can still send them emails. It would be a huge problem if I’d need an email account with every provider that I wanted to send emails to. That I can use one account to send email to anyone that reads email is an advantage for me.

Disable comments on your blog

Wed, 13 Apr 2011 14:13:21 +0200

David Siegel tweets:

Looking to make a positive change in your life? Disable comments on your blog.

When you want to respond to a blog post, get your own blog and write a blog post there.

Which program listens on a port?

Wed, 13 Apr 2011 13:13:12 +0200

Let’s say you run nmap on your local box and you see an open port, but don’t know which program is listening on that port. Wouldn’t it be great to be able to find out? The program you need to find this information is lsof, or list open files. This program can show you a lot of information about open files, ports and directories.

Let’s go back to the original question. Run the following command.

Log parsing speed

Wed, 13 Apr 2011 11:36:00 +0200

Now that we have two programs that parse log files, we can start to take a look at how many lines the program parses per second. First we have to make the two programs as similar as possible. In pseudocode it looks likes this.

Load all modules
Take the start time using Time::HiRes
Put the code of the program here
Set line_count = 0
Using stdin: loop through all lines
1. Parse the line
2. Set line_count++
Find the time difference
Divide and line_count / time as n lines/s

In Perl this looks like:

Write your own Accesslog parser in Perl

Tue, 12 Apr 2011 20:59:27 +0200

Writing an apache access log parser isn’t that hard. Below is a parser that does just that. It creates Data::Dumper output of all the lines. No warranty.

use Data::Dumper;
use Parse::RecDescent;

$Parse::RecDescent::skip = '';

my $grammar = q{
line: ip ws '-' ws user ws datetime ws request ws status ws responsesize
            ws referrer ws useragent "\n"
{ $return = {
            ip        => $item[1],
            user      => $item[5],
            datetime  => $item[7],
            method    => $item[9]->{method},
            url       => $item[9]->{url},
            protocol  => $item[9]->{protocol},
            status    => $item[11],
            size      => $item[13],
            referrer  => $item[15],
            useragent => $item[17],
        } }
user: '-' | /\w+/
request: '"' method ws url ws protocol '"'
    { $return = { method => $item[2], url => $item[4], protocol => $item[6] } }
datetime: '[' date ':' time ws timezone ']'
    { $return = $item[2] . ' ' . $item[4] . ' ' . $item[6] }
status: /\d{3}/
protocol: 'HTTP/' version
method: 'GET' | 'POST' | 'PUT' | 'DELETE'
ws: /[ ]+/
url: /\S+/
referrer: quotedstring2
responsesize: '-' | /\d+/
useragent: quotedstring2
date: day '/' month '/' year
    { $return = join('/', $item[1], $item[3], $item[5]) }
day: /\d+/
month: 'Jan' | 'Feb' | 'Mar' | 'Apr' | 'May' | 'Jun' |
    'Jul' | 'Aug' | 'Sep' | 'Oct' | 'Nov' | 'Dec'
year: /\d{4}/
time: /\d{2}:\d{2}:\d{2}/
timezone: ('+'|'-') /\d{4}/  { $return = $item[1].$item[2] }
octet: /\d+/
ip: octet ('.' octet)(3) { $return = $item[1] . '.' . join('.', @{$item[2]}) }
version: /\d.\d/
quotedstring2: '"' /[^"]+/ '"'   {$return = $item[2]}
};

my $parser = Parse::RecDescent->new($grammar) or die "Bad Grammer";
while (<>) {
    my $ret = $parser->line($_) or print "Parse error\n";
    print Dumper($ret);
}

Apache accesslog reporting tools

Tue, 12 Apr 2011 11:36:31 +0200

Today I tried to create a report of some basic statistics about Abacus downloads. Normally I would use grep, awk and a few other commandline tools to find a rough estimate of these numbers. However this time I needed a bit more information than these tools could give me. A problem in need of a solution.

My first question was: how many people have downloaded Abacus? The answer is

grep '/abacus/files/Abacus' | grep -v '<localip>' \
    | grep -v 'somebots' | awk '{print $1}'
    | sort | uniq | wc -l

The pattern here is the following. First find the lines you want. Then remove the lines you don’t want. Print the first field-the client-and makes this list unique. I don’t want to count multiple downloads from the same ip.

F*ck you, pay me

Tue, 12 Apr 2011 09:24:05 +0200

I’m aware that this is really obvious to some of you. I link to a video here of a presentation by Mike Montiero of Mule Design about how to get clients to pay you for your services. If you work with clients then you should watch this. It’s about how it should be done. Just good advice.

Then after you enjoyed the video, you should listen to this interview of Mike Montiero by Dan Benjamin.

Not locked up in your phone or email

Mon, 11 Apr 2011 22:52:18 +0200

In the first 5 minutes of the video The Storage Technologies Behind Facebook Messages the bald manager talks about messages and shoeboxes, and how he can’t have all his messages in one place. He says: “Where is my box of letters? It’s locked up in a phone, it’s locked up in email. It’s not in one place. Until now.” The one place being Facebook. So I ask, how is it better if we lock up all our messages in Facebook?

The parts of Realtime RSS

Sun, 10 Apr 2011 17:48:49 +0200

Friday night I implemented a new feature for my Pompiedom empire for realtime RSS feeds. At some point on saturday I realised that I had made a small mistake (it depends how you look at it, of course).

Today I thought a bit about the different parts of a Realtime RSS ecosystem and I found the following parts

The cloud, a mechanism for subscription and notification of feeds. You can subscribe to a feed and the cloud will send a notification if something changes.
Storage, stores new feed items and provides feeds to readers. Pings the cloud if a new item is added.
Authoring, an interface for create new items in a feed. Sends the new items to the storage.
Reading, tools for reading the feeds and can be notified by the cloud when new items appear in feeds.

Parts of this system can be combined into one program, but it’s not needed, because of the protocols that are used. Each part can be a separate program and multiple programs can implement the same part.

Names are important for being specific

Thu, 07 Apr 2011 21:43:56 +0200

I read an article from the BBC website that talks about how Net giants challenge French data law. The article isn’t very specific about what the law actually contains. There also isn’t a link to the text of the law or the name (or number if you will) of this law. So while this creates a lot of commotion on Twitter, there is no way to search for the text of this law. The only name we got is ‘french data law’, which is in my opinion not very useful.

Cursor blinking in Ubuntu

Thu, 07 Apr 2011 17:32:46 +0200

I’m not sure when it happened, but yesterday and part of today I found myself in the company of a blinking cursor. Normally blinking cursors are not a big problem. The thing is, however, that when I’m writing code, or text in my favorite text editor, I want to know where the next character I type will land on the screen. With this blinking cursor, it seemed my mind started to blink in unison. Not very useful when trying to write.

Create sub directories in Perl

Thu, 07 Apr 2011 11:44:45 +0200

Sometimes you need to create a large tree of subdirectories. But why? Two examples that I think of are structured directories for weblogs, e.g. /[year]/[month]/[day]/, or the automatic backing up of files e.g. invoices/[company]/[year].

Before you begin, you know that using a split and chdir, or some other combination of built-ins, will just make big mess. A call to mkdir -p could also work, but let’s use the available modules this time.

Just for reference: Firefox keyboard shortcuts

Wed, 06 Apr 2011 19:09:35 +0200

A list of [Firefox keybindings](http://support.mozilla.com/en-US/kb/Keyboard shortcuts). I couldn’t find this list, because I was searching for key bindings.

Creating thumbnails with Windowpipe

Wed, 06 Apr 2011 16:18:10 +0200

Yesterday I created a small program called Windowpipe. IT allows you to drop files in a window and it will a script on that file. To give you a better idea of how this works, I created a small screencast.

So what’s happening? First I drag the shoes.jpg file to the windowpipe window, which I started before with createthumb.pl. After the drag a new file is created called thumb_shoes.jpg. Then I show the two files. Simple.

Drop files on a window and run a script

Tue, 05 Apr 2011 11:48:18 +0200

The premise is simple: create a window the runs a script on the items that were dropped on the window. Simple idea, simple program. I took a first crack at it and uploaded the code.

The first release just runs a script and passes the dropped thing.

Let's start a programming news network

Mon, 04 Apr 2011 23:23:24 +0200

I have been building a system of posting short posts on top of RSS and rssCloud. This system helps people to create link blogs and short posts about anything they like. Now I was thinking maybe we can build a programming news network on top of this system. There are already two systems that I know of that work with this system. One is my own, called Pompiedom. The other is the system created by Dave Winer.

How I use Google Reader

Mon, 04 Apr 2011 21:00:13 +0200

I like it that I have to deal with every item in Google Reader. I think it is a good way to do a river of news, especially if it is sorted oldest to newest. Dealing with these items is really simple.

Google Reader sorts my items from oldest to newest and I view every item in turn. To go to the next item I press ‘J’. This way I can skim every item. If I find something that I want to read (especially if it’s longer) I open it in a new tab.

Make the location implicit

Sun, 03 Apr 2011 13:40:16 +0200

URLs are the addresses of the internet. Each URL points to a location and your user can go there. However on the internet the addresses are not that important to the users and browsers. Especially since we can read almost any page on such a location. So the location doesn’t matter as long as we find what we expect.

The URL and the link text both build an expectation in us. The text and the URL will imply what we will find after we click the link. I think it makes sense to write links without showing the URL.

List folders in a Maildir for mutt

Fri, 01 Apr 2011 10:14:43 +0200

find . | awk -F/ '{ print $2 }' | sort | uniq |\
   grep '^\.' | sed -e 's/^./+./'

Pompiedom River UI

Thu, 31 Mar 2011 16:35:38 +0200

The new River UI looks like this:

Small interface

Clicking the What’s happening field will open the whole form:

Whole river form

Difference between Firefox and Chrome handling of CORS

Thu, 31 Mar 2011 16:04:46 +0200

In Cross-Origin Resource Sharing:

Why can cookies and authentication information not be provided by the script author for the request?

This would allow dictionary based, distributed, cookies / user credentials search.

If you send a username and password when using withCredentials, then XMLHTTPRequest.send(...) will fail in Firefox 4, but not on Chrome 11.0.696.16 dev. Removing the username and password will make it work on both of them.

I haven’t tested other versions.

HTML5 Audio

Tue, 29 Mar 2011 00:15:32 +0200

Today I was working on river again and after I added enclosure support I wanted to add a way to play audio files. The first thing I thought was, we can I find an inline mp3 player. And while I went to Google another idea popped into my mind: HTML5 audio.

So I added the tag:

<audio src="url" />

And without much more effort I had working audio playback in my river. How easy is that?

Pompiedom river

Sun, 27 Mar 2011 22:02:55 +0200

My river includes a way to add new posts to my personal feed.

When I click on the textarea, it grows and shows two optional fields where I can add a Title and Link for this post. Clicking Publish will send the post to my posting interface on the server using AJAX.

A new post appears within a few seconds in the river below. Posts from other feeds also appear in the river within seconds of being posted.

My Plack rssCloud code

Sun, 27 Mar 2011 20:16:26 +0200

I forgot to include the link to my rssCloud in the last post about how I wrote one in Plack.

Can't play with Twitter

Sun, 27 Mar 2011 20:14:06 +0200

In Tweeting about Twitter’s Terms Dave Winer writes:

You can’t be half in and half out. Either you connect to Twitter, and they own you and your users, or you don’t connect to Twitter.

So we can’t play with Twitter, but the other way around Twitter can’t play with us. At some point in the future rssCloud based microblogging clients will take off and Twitter will have to change their terms of service to allow us to let them play with us. At that point we won’t care anymore.

Camlistore use cases

Fri, 25 Mar 2011 18:50:04 +0100

The use cases of Camlistore or all very interesting. I’m interested to see how this all pans out.

Camlistore

Fri, 25 Mar 2011 18:09:04 +0100

Camlistore seems like a really cool project when it gets farther along. Or actually it seems really cool already, but it’s not useable at the moment. Something to take a look at sometime in the future.

I wrote a Perl RSScloud

Sat, 19 Mar 2011 16:35:35 +0100

Today I wrote an rssCloud in Perl. It uses Plack and AnyEvent. That it uses Plack doesn’t at the moment mean that it works with any Plack compatible web server. It works with Twiggy, but doesn’t with HTTP::Server and others. This relates to the AnyEvent code.

I followed Dave Winer’s walkthrough for implementation information and looked at some of the frontend parts of his system.

At the moment it only supports the http-post protocol for subscription and ping. This shouldn’t be too big of problem I hope. Everyone who is interested and able should send me a patch for the XML-RPC part. Patches are welcome!

Microblogging DIY

Tue, 15 Mar 2011 23:50:25 +0100

I am building my own microblogging tool. It uses RSS and RSScloud to get realtime updates from the web. Tonight I got it working and now I need some feeds to parse. Yesterday I already saw that Identi.ca provides RSScloud feeds, so I tried one of them out.

The first feed I added was my own. The test to see if it worked was posting a message to my account. And … a post appeared in my microblogging client in realtime. It only took two seconds between a post on identi.ca and the receive on my end. Really nice.

Testing If-Modified-Since with lwp-mirror

Sat, 12 Mar 2011 12:37:50 +0100

This week I created a way for me to post small messages, as there is not yet a good decentralized way to make this happen. One part of this research is how can I create, host and share RSS feeds without using to much bandwidth and server time.

One way we can do this, is by using the features of the HTTP protocol. One of those features is the Last-Modified header. This header allows web servers and user agents to see when a resource was last modified. Together with a If-Modified-Since header we can let our software check if it needs to send the whole body or just the a simple 304 header.

Cacti doesn't show the graphs in the graph view

Wed, 09 Mar 2011 11:23:18 +0100

Just for reference, maybe somebody can find some use for this.

I installed Cacti, I added a few graphs, but I couldn’t see the first page of graphs in the graph view. I could click on the graphs and I would see all graphs, just not the first page.

After searching for problems I found the following line in my /var/log/apache2/error.log log file.

ERROR: I don't understand ':15:00 To 2011/03/09 10:15:00\c' \
  in command: 'COMMENT:From 2011/03/09 09:15:00 To 2011/03/09 \
  10:15:00\c'.

This problem can be fixed by choosing the right version of RRDtool in your cacti Settings. So change Settings > RRDTool Utility Version to ‘RRDTool 1.2.x’.

Abacus is Free Software

Thu, 24 Feb 2011 15:49:11 +0100

I just released Abacus as Free Software. The source code can be found at GitHub.

Watch the screencast

This is just a release for the license change.

Also, I’m looking for people who like to provide patches to make Abacus the best calculator for Windows and Linux. Like to help? Send me an email or message me on Twitter.

Web 2.0 privacy paradox

Mon, 21 Feb 2011 11:39:31 +0100

With Eben Moglen’s Freedom Boxes in our minds, I will paraphrase Danny O’Brien, who talked about the Web 2.0 privacy paradox in his Living on the Edge talk.

When you want share a private message with just one person (or some other group of people), you first have to give this message to a Faceless Corporation, which will make sure that only their servers and that other person will see this message.

Freedom in The Cloud

Sun, 20 Feb 2011 22:44:55 +0100

Eben Moglen in Freedom in The Cloud (around 24:50):

The human race has susceptibility to harm but Mr. Zuckerberg has attained an unenviable record: he has done more harm to the human race than anybody else his age.

Because he harnessed Friday night. That is, everybody needs to get laid and he turned it into a structure for degenerating the integrity of human personality and he has to a remarkable extent succeeded with a very poor deal. Namely, “I will give you free web hosting and some PHP doodads and you get spying for free all the time”. And it works. Transcript.

No comments on my weblog

Sun, 20 Feb 2011 22:21:55 +0100

In the past people could leave comments on my weblog. At the moment people can’t leave comments anymore.

Still there are people who would like to respond or write about an post that I’ve written. The best way to respond is to write a post on your own weblog and link to the post that you like to respond to.

If this feels like a lot of work, you’re probably right. However it does give you some time to think about your response. It give you a bit of time to write a thoughtful response instead of some small blurp. And you expose your readers to another article about a topic, that you care enough about to write a thoughtful response.

On Tickets and Order Processing

Tue, 25 Jan 2011 12:07:00 +0100

At some moments in time, ideas come together in a mind to form a new idea. The baffling part is the realization that the idea has been hanging around you for some time (years, sometimes).

Such an idea can be really obvious in hindsight. My latest big idea came to me last week, when I had added the ability to add comments to orders in my webshop software. Simple enough, you might think. And you would be right.

How articles could disappear

Mon, 03 Jan 2011 12:07:48 +0100

A small list of ways how articles (or documents) will disappear at some future point in time.

User error removes the originals
User error removes the generated files on the server
Hard disk failure (on server)
Hard disk failure (on author)
Backup failure (one, two and three)
Server failure
Hosting company out of business
Domain name registrar out of business
Media company out of business
(Author’s) Death
Lack of interest
Lack of technical expertise
Removed everything in anger
Revisionism
Changed interests
Cost savings
Changes in publishing software
Conversion costs
Backwards incompatible software changes
Changes in laws

On the Fragility of the Internet

Mon, 03 Jan 2011 12:05:53 +0100

The internet is an amazing place. Read the news, follow your favorite writers, hang out with your friends, watch videos and fall in love. It’s all possible on the internet. It feels as if it was there forever and it will never go away.

However with every click of your mouse or key press on your keyboard, you chip away at the internet. With every byte you send and receive the hardware of the internet becomes a little bit worse. One day the hard disk on which a web page is stored, needs to be replaced and a copy needs to be made.

Twitter's Pavlovion dogs

Mon, 06 Dec 2010 22:25:27 +0100

I tweeted about it before: I think the Twitter website isn’t realtime, because the little number in the title of the webpage makes people click the blue label that shows there are new tweets. It therefore increases the engagement on the Twitter website.

If I have Twitter open in my browser I will click the blue box to get a few pellets with new tweets. I can’t help it. It’s also the main reason not to use the Twitter website (apart from this I actually quite like it).

Anti-Fragility

Thu, 25 Nov 2010 16:54:29 +0100

Anti-Fragility is an amazing idea. How can this be used in software and other computer systems?

Taleb on Anti-Fragility

Not intended to provide medical advice

Wed, 17 Nov 2010 17:44:22 +0100

US Scientists Significantly More Likely to Publish Fake Research, Study Finds:

This article is not intended to provide medical advice, diagnosis or treatment.

Really?

Shipping something, anything

Sat, 13 Nov 2010 13:28:05 +0100

I just read this piece by Marc Hedlund, in which he says Shipping Solves Everything. He says:

I’ve always found that shipping something, anything, is the biggest help. Even just shipping a blog post.

I think this is right. It works great with the thing, I would like to call Small Victories. A Small Victory helps you get some feedback and some new ideas and energy for working on your things.

Aptitude why

Thu, 11 Nov 2010 12:51:13 +0100

Sometimes you find packages on your Ubuntu box and you don’t know how they got there. This happens often with automatically installed programs. To find the packages that require (or recommend) another package, you can use the aptitude why command.

Below you see (an edited) example session where I needed to find the program that used a package.

$ aptitude search timidity
i A timidity        - Software sound renderer...
i A timidity-daemon - runs TiMidity++ as a sy...

In this example I first search for the package that I didn’t know and wanted to remove. You can see from the uppercase A that this package is installed automatically. First I need to know if the program is system critical. So I use the why command to find the packages that use this package.

Google's problem

Wed, 03 Nov 2010 22:21:12 +0100

What if the bottleneck of your software isn’t in your CPU, memory, network or I/O throughput, but in that of every website on the internet?

When you encounter a bottleneck you can do a few things. I will list two.

Optimize your software or processes.
Increase the resources that limit the system.

The question is what can you do when your software and processes are optimized and your resources are increased to the point where they don’t limit your system. In other words optimizing software and adding more resources have a negligible effect.

Dear readers, who are you?

Tue, 02 Nov 2010 16:02:36 +0100

With thanks to Startup Lessons Learned for the idea.

Small four question survey

Product pages in webshops

Tue, 19 Oct 2010 16:25:56 +0200

Dividing a product list into multiple numbered pages provides no extra functionality to customers. It in fact hinders the customers to find the product they want.

The easy way out

From a customer, webshop (and database) point of view, the natural way to show products is by not dividing the products at all. Just show all products on one page.

However at one point, there will be to many products in a list. The list will contain many products and the webshop software doesn’t allow better ways to divide the products. The easy way to solve this problem is by creating multiple pages all with some of the products.

Another editor?

Sat, 02 Oct 2010 16:28:35 +0200

From neugierig.org:

A UNIX wizard hears cries of torment from his apprentice’s computer room where the apprentice is studying, and goes to investigate.

He finds the apprentice in obvious distress, nearly on the verge of tears. “What’s the problem?” he asks. “Why did you cry out?”

“It’s terrible using this system. I must use four editors each day to get my studies done, because not one of them does everything.”

The wizard nods sagely, and asks, “And what would you propose that will solve this obvious dilemma?”

Template 'table' filter

Tue, 14 Sep 2010 01:19:11 +0200

After these two changes I got into an object-oriented (with a splash of functional and generic programming) mindset. So I created a table filter in my template code. A filter is a function that transforms a data structure to an HTML string.

This filter transforms a template parameter value from an arrayref to an HTML table. Currently it only supports lists of items, but it could be expanded to single items. I’m not sure how useful that would be, however. The question is: “How can we produce a nice HTML table from an arrayref?” The answer lies in the use of objects.

Proposal for handling 403 forbidden

Sat, 11 Sep 2010 12:01:29 +0200

While I was thinking about how to structure some of my access handling code in my web app, I saw that it currently is impossible to return a 403 code when a user reaches a password protected page.

The biggest problem with returning a 403 is the way the browsers show this problem to the user. The user is interrupted with popup asking them for a username and a password.

Middleware in Plack

Fri, 10 Sep 2010 22:15:18 +0200

I’ve been using Plack for a few days now, and I have to say, I really like it. I rewrote the base of my webshop platform to use it. The change wasn’t really difficult and the code is a lot cleaner now.

Especially with the Middleware structure I was able to remove a lot of code from the main application. Middleware classes are classes that are called between the webserver and the main application. These classes have the opportunity to rewrite the request and the response classes for each request.

Hash function performance

Fri, 10 Sep 2010 13:06:00 +0200

In Hash function performance Dave Winer writes:

It’s been a long time since we looked at the object database in Frontier, so today Brent wrote a little app that checks out how the hash function distributes objects across the buckets for each table in the database.

[… result distribution among buckets …]

This looks pretty random to us.

And he’s right. In the sense that it’s just a bunch of random numbers. Not something you would want in a hash function.

Dijkstra's EWD1036

Wed, 08 Sep 2010 15:17:30 +0200

I’m really not sure what to say about EWD 1036. This is a must read for people who think we can write better software programs.

Programming will be so different in the future, that people will talk about this time, as the great false start or the Dark Ages of programming.

The coming age (I don’t think it has started yet), will be based on mathematics. The software we write will have sturdy theoretical underpinnings that will evolve with the software we write. Where formal methods seem unwieldy now, we will see ways to simplify these. We will prove theorems about structures and these structures will be used again and again. We will find structures in our programming languages and programs and simplify and use these structures from one program to the next.

Executing code from templates

Tue, 31 Aug 2010 23:03:38 +0200

Until today I couldn’t use variables in my template that are pieces of code. I added one piece of code that executes the piece of code in a the stash and returns its value. In the template it looks like this.

[% FOR p IN products %]
    <p>[% p.name %]
[% END %]

There are two places in this piece of code that could contain code references. The first is products. This could be implemented as follows.

Problems while measuring performance

Fri, 27 Aug 2010 11:18:41 +0200

While browsing around StackOverflow I found a page about Square root function implementation. One of the answer points to an article containing different implementations of square root.

One of the things I like to do is pointing out obvious errors in benchmarks. It’s not that I don’t have an intimate understanding of these things, but if I can point out the error, is has to be obvious. One of the obvious errors in time measurement can be shown using a short pseudo code example.

Controllers and actions

Thu, 26 Aug 2010 23:50:53 +0200

In the last two essays we established that there is a dispatcher, multiple controllers and multiple actions. The dispatchers creates a controllers and calls the action. Why do we split the application into these parts?

First the Dispatcher. The Dispatcher applies rules to a URL and chooses the corresponding Controller and Action. The Controller is a container for action and applies some default values to the action. The Action contains the code that’s necessary to perform some transformation on the application data.

The structure of dispatching controllers

Wed, 25 Aug 2010 21:17:47 +0200

Yesterday we looked at the structure inside of two simple controller actions. Now let us look at the outside. The structure of the two actions can be shown as a tree.

Guestbook
- list
Orders
- list

I hid the rest of methods that would normally be in these controllers. In front of these controllers there is another class, called the Dispatcher. This Dispatcher uses a request and calls the appropriate controller and action.

Discovering structure in web controllers

Tue, 24 Aug 2010 21:47:11 +0200

Alex Stepanov writes in Notes on Programming:

We often get the idea that a mathematical theory is built in a logical way starting from definitions and axioms. This is not the case. The definitions and axioms appear at the very end of the development of a good theory. It invariably starts with simple facts that later on are generalized into theorems, and only at the very end the formal definitions and axioms are developed.

Math every day

Mon, 23 Aug 2010 10:09:29 +0200

Steve Yegge wrote (and writes, again) about interesting stuff. Two of my favorite essays are written by him. One is about Compilers and why you should know them, the other about why it’s important that programmers learn mathematics. Read them both to better understand where I come from.

I came to the conclusion that saying mathematics has nothing to do with programming, is like saying programming and software contain no patterns or structure.

Automated screenshots in Firefox with WWW::Mechanize::Firefox

Thu, 19 Aug 2010 10:54:29 +0200

I was reading presentation slides from YAPC::EU 2010 and found this one: Web Automation with WWW::Mechanize::Firefox. It explains a module that connects to a running Firefox instance and will use it to follows links, create screenshots and more.

I rewrote the example a little bit make it work. I ended up with the this. These are two methods that work. The original method didn’t work for me

# The original line in the example
my $png = $mech->content_as_png();

# Method 1
my $png = $mech->element_as_png($mech->selector('html'));

# Method 2
my $png = $mech->content_as_png(undef,
                {left=>0,top=>0,width=>200, height=>200});

Now I can automatically create screenshots from webpages. I will still need some way to control the width of the page and maybe a way to crop parts. I could use the element_as_png method for cropping, which allows me to get a screenshot of part of a page, maybe that’s enough.

Generic Programming, STL and Stepanov

Tue, 17 Aug 2010 22:07:05 +0200

Here are two talks about Generic Programming, that I like very much. Generic Programming is about much more then just C++ templates.

Alexander Stepanov: STL and its Design Principles

In this first talk Stepanov talks about concepts and not much about STL. As he says (paraphrased): STL is maybe the biggest library of its kind, but it’s just a small step in Generic Programming. There is much that can be done with Generic Programming, STL is just the beginning.

Hey, I was using Wave

Thu, 05 Aug 2010 09:18:50 +0200

Update on Google Wave:

Wave has taught us a lot, and we are proud of the team for the ways in which they have pushed the boundaries of computer science. We are excited about what they will develop next as we continue to create innovations with the potential to advance technology and the wider web.

It’s sad that Google Wave was cancelled. I use it every day. And altough I have to admit that there are some problems with it, it is an amazing web application for collaboration between a few people. I wrote some project plans and lists of todo items. Other people commented and rewrote posts and I did the same.

Fat milk actually not that bad

Wed, 04 Aug 2010 19:25:04 +0200

New study suggests full-fat milk might be better:

We find that the persons who consumed the highest amount of full-fat dairy had a 70 per cent reduced risk of dying from cardiovascular disease, compared to people who do not eat full-fat dairy; so that’s quite a large effect.

Suntory whiskey scene from Lost in Translation

Tue, 03 Aug 2010 13:19:15 +0200

Translation from Lost in Translation:

DIRECTOR (in Japanese to the interpreter): The translation is very important, O.K.? The translation.

INTERPRETER: Yes, of course. I understand.

DIRECTOR: Mr. Bob-san. You are sitting quietly in your study. And then there is a bottle of Suntory whiskey on top of the table. You understand, right? With wholehearted feeling, slowly, look at the camera, tenderly, and as if you are meeting old friends, say the words. As if you are Bogie in “Casablanca,” saying, “Cheers to you guys,” Suntory time!

Remembering through use

Mon, 02 Aug 2010 12:22:49 +0200

This is an old story about young people that can’t remember as much as old people:

This summer, neuroscientist Ian Robertson polled 3,000 people and found that the younger ones were less able than their elders to recall standard personal info. When Robertson asked his subjects to tell them a relative’s birth date, 87 percent of respondents over age 50 could recite it, while less than 40 percent of those under 30 could do so. And when he asked them their own phone number, fully one-third of the youngsters drew a blank. They had to whip out their handsets to look it up.

Sorry, I wasn't here for your birthday

Mon, 26 Jul 2010 14:29:25 +0200

I’ve been writing this weblog for six years and fourteen days now. That’s how long ago I started writing here. It probably is the longest running website, that I have created. Sure, there were changes, like the one from a few days ago, when I removed almost all formatting.

But there are more changes. While building this weblog I created a small software tool called pages that creates and generates the pages and posts for this weblog. In the beginning the pages where created using a small Emacs function. I haven’t used Emacs for anything for almost five years now. I can’t even use it anymore, Vim is baked into my muscle memory. It’s a disorienting feeling, to say the least.

Software Patents

Thu, 15 Jul 2010 14:44:12 +0200

John Carmack on Software Patents:

The idea that I can be presented with a problem, set out to logically solve it with the tools at hand, and wind up with a program that could not be legally used because someone else followed the same logical steps some years ago and filed for a patent on it is horrifying.

I am my own god

Mon, 05 Jul 2010 10:46:40 +0200

Charles Bukowski:

For those who believe in God, most of the big questions are answered. But for those of us who can’t readily accept the God formula, the big answers don’t remain stone-written. We adjust to new conditions and discoveries. We are pliable. Love need not be a command nor faith a dictum. I am my own god. We are here to unlearn the teachings of the church, state, and our educational system. We are here to drink beer. We are here to kill war. We are here to laugh at the odds and live our lives so well that Death will tremble to take us.

Doubt

Mon, 05 Jul 2010 10:39:29 +0200

Richard Feynman on doubt and uncertainty:

You see, one thing is I can live with doubt, uncertainty and not knowing. I think it’s much more interesting to live not knowing then to have answers which might be wrong.

I have approximate answers and possible believes and different degrees of certainty about different things, but I’m not absolutely sure about anything and many things I don’t know anything about. Whether it means anything to ask, why we’re here. What that question might mean? I might think about it a bit. If I can’t figure it out, then I go on to something else.

Minimalism

Mon, 21 Jun 2010 12:48:25 +0200

In photos it seems like minimalism is white and black designer furniture. I argue that this isn’t very minimal. Minimalism is something that’s inside of you. In the same way that GTD is about emptying your mind, minimalism is about minimizing the effect of the outside world on your inner mind.

Expensive designer furniture may reduce the effect of your busy environment, but it will also increase the worry for the moment that you drop a cup of coffee on its white fabric.

Calculators on computers

Sun, 30 May 2010 17:17:11 +0200

I created a new calculator. This short video shows how it works. I use it more often than calculator that’s included on my computer.

This calculator doesn’t use buttons for input. It uses the keyboard instead. You can type a normal formula and the calculator will give you the answer while you type. You can find more information about it on stuifzand.eu/abacus.

Search and exclusion

Thu, 27 May 2010 14:27:09 +0200

Google is amazing for searching the public web. It contains all the weblogs, websites, videos, and images that are shared by everyone. Everything Google can get its hands on, will sometime or another be found by someone that searches for it.

The problem for Google however is, is that it can’t cross the borders that are created by some websites, like Facebook or Hyves. And sometimes the borders are really low. If there is a just a little border, Google can’t get to it.

Ubuntu 10.04 LTS Lucid Lynx released

Fri, 30 Apr 2010 13:48:42 +0200

Canonical just released the latest version of Ubuntu.

I haven’t tried it yet, but will when things calm down here. At the end of April and the beginning of May there are a lot of parties in the Netherlands, e.g. Queensday and Liberation Day.

Perl 5.12 has been released

Tue, 13 Apr 2010 09:47:19 +0200

The latest version of Perl, version 5.12 has been released. There are many changes and bugfixes and I would recommend you check the release notes for the whole list.

Implicit strictures when you use an version number greater than 5.12.0
The yada, yada operator
Y2038 compliance
New package naming for including the version
Updated to the latest Unicode standard

Gearman released version 0.13

Wed, 07 Apr 2010 10:42:35 +0200

Gearman released the latest version, 0.13, of the gearman server and C libraries. It contains a various bug fixes.

Gmail buttons changed?

Tue, 06 Apr 2010 20:08:18 +0200

I just noticed something: the Gmail buttons have changed.

The corners of the buttons are rounder now. I don’t have an image of the previous buttons, only the article by Douglas Bowman about the design of the buttons.

Pagination on the web

Mon, 29 Mar 2010 23:32:58 +0200

People write blog posts. And when you have written a lot of blog posts, there comes a time when it becomes necessary to divide the posts into smaller collections of posts. One way to do this is pagination.

Pagination divides a list of items into a few pages. Each page has an URI, contains a few items and links to other pages in the list.

There are many places where this method is used. Two examples are search result pages and blogs. Search result pages can contain many, many results, sometimes as much as a few million. Showing all the result is a waste of space and bandwidth, as most people won’t even look past the first page.

Living on the Edge

Mon, 22 Mar 2010 10:57:09 +0100

It becomes more and more apparent that we need to work on software and hardware that will allow us to our own version of services that we use online. We need a kind of home server computer that acts like a telephone. Every home needs one and (I’m predicting) will have one in ten years.

This presentation by Eben Moglen about Freedom in the Cloud talks about how we, as geeks and software developers, can accomplish this goal a bit faster. It really isn’t that hard. We should start building these home server devices and iterate and search useful features, that will help people find what they need and how it can help them in their lives.

Design = Beneficially Relating Elements

Wed, 10 Mar 2010 14:28:05 +0100

Inspired by the “Benificially Relating Elements” phrase of Kent Beck, I started out creating a builtin weblog for my webshop platform. The nice thing about the idea is that it helps you find relations between elements that you already have.

I started with the “What is a weblog?” A weblog is a chronological list of pages. By answering this way, I can reuse two elements that already are supported in the webshop: collections and pages.

Use perl 5.10: Given / when

Mon, 08 Mar 2010 23:33:24 +0100

The feature I’ll talk about here is the given/when construct, which was added in perl 5.10. It works like switch/case in other programming languages, but is much more powerful. The matching is based on smart matching, which is another feature added in 5.10;

I will start with a simple example to give you an idea of the syntax that is used.

use 5.010;

my $x = <>;
chomp $x;

given ($x) {
    when ([0..99]) {
        say "Looking good";
    }
    when ([100..199]) {
        say "That's a bit much";
    }
    default {
        say "This could be a problem";
    }
}

This code compare the value of $x with the array’s in the when statements. If $x is between 0 and 99 (inclusive) it will the text Looking good. If it’s between 100 and 199 then it will say That's a bit much. The default block will be called when the value isn’t matched by the when blocks.

Testing for improvement

Tue, 02 Mar 2010 09:36:07 +0100

When I’m programming, I sometimes need to use a problem solving pattern, that Kent Beck called Parallel. The pattern tells us that when your making a change you should also leave the old way of doing things in the program, so you can gradually move to the new solution. This helps in situations, where you can’t just flip a switch to migrate.

The problem with this however is, that you do have to migrate all the way to the new solution, because otherwise you will have twice the code and data in various states.

Pasta and leeks

Sun, 28 Feb 2010 20:55:40 +0100

Sending email with Perl in 2010

Wed, 24 Feb 2010 16:24:04 +0100

Example of how you should send email in 2010 with Perl.

#!/usr/bin/perl -w
use strict;

use Email::Sender::Simple qw(sendmail);
use Email::Simple;
use Email::Simple::Creator;

my $email = Email::Simple->create(
    header => [
        To      => '"Peter Foo" <foo@example.com>',
        From    => '"Peter Bar" <bar@example.org>',
        Subject => "What's up",
    ],
    body => "Hey, how are you doing?",
);

sendmail($email);

You can see that this is simple enough. First you create an Email::Simple object. This object will format the message that wil be sent.

Help prove help you

Wed, 17 Feb 2010 10:34:54 +0100

I use prove from Test::Harness to test the code of my Perl projects. The program prove runs tests files and summarizes the output. If tests fail then it shows the error in its output.

The problem is, my defaults aren’t the same as the defaults that prove uses. I keep my main application files in app/lib and a few vendor libraries in vendor. The problem with this is that I have type out the options of prove every time I wanted to test. For the longest time I used a Makefile to solve this problem.

Buzz paper cuts

Tue, 16 Feb 2010 10:40:22 +0100

In the same way that Ubuntu has a list of problems that are trivially fixable Paper cuts, you could also do that for other programs. Google Buzz is a service that I use at the moment. I like this program, because it seems to take public standards into account and it will allow decentralized communication between people. So today I will spend some time to write down the few problems that I found that will be trivially fixable.

Using user-generated HTML on webpages

Sat, 13 Feb 2010 14:42:04 +0100

Jeff on Coding Horror writes:

Among programmers of any experience, it is generally regarded as A Bad Idea (tm) to attempt to parse HTML with regular expressions.

You should read the rest of the article. I’m mostly of the same opinion about this as Jeff. Additionally I think that parsing HTML is a bad idea in the first place.

One of the examples Jeff gives for parsing HTML is sanitizing user input. The user input will be used on the website as comments for example. I think allowing people to write HTML and putting it on a webpage is the wrong way to go.

I would have lost interest somewhere between...

Fri, 12 Feb 2010 13:23:17 +0100

Adam Turoff wrote:

I could have written my taxicab number search in C or Java, but I would have lost interest somewhere between #include <stdio.h> or public static void main(String args[]) and firing up the compiler.

It’s a shame this happens so often. It should be easier to just write the part your idea is about and then insert it into some thing, that will make the rest work.

The problem with Wave (and other things)

Fri, 05 Feb 2010 11:24:12 +0100

A few days ago I started using Wave for some real projects. I found out that Wave is not really hard to use. The problem is that the network effect is kicking in, but in the opposite way.

Wave is a communication tool. You can use it to send messages and collaborate on projects with other people. And I think the problem here, is that the other people are missing.

Simple tool for finding an external ip address

Wed, 03 Feb 2010 11:36:02 +0100

I just released a small program that gets the ip address or your computer. The nice thing is, this service is REST-based.

You can find it at Stuifzand Software Tools.

Programmers and the iPad

Sat, 30 Jan 2010 20:07:32 +0100

It seems a few people wrote that they wouldn’t have learned to program as a kid on an iPad instead of a real computer.

The things is that no one thought this was a problem with the iPhone or the iPod Touch. People think of those as a computer, but not, as a real one. The conclusion could be this: for a device to be a computer, it needs to be programmable on the device itself.

On a blog I can publish anything

Fri, 29 Jan 2010 16:53:11 +0100

The cool thing about a blog is, that I can publish anything that I want. If I want to favorite a video on a video sharing website, it needs to implement that for me. On my weblog I can post it just as easy.

Weird or just different?

Fri, 29 Jan 2010 16:43:30 +0100

Email accounts become user accounts

Fri, 29 Jan 2010 15:49:33 +0100

I just read something that seems really nice. It’s even strange that it isn’t already used like that. Use an email address-like identifier as pointer to an account. Let me explain.

Email addresses consist of two parts seperated by an @-sign. The first part is the username, the second part is the domain name of your email provider. For example, my email address is peter@example.com. The username is peter and the domain name is stuifzand.eu.

iPad and programming

Fri, 29 Jan 2010 13:47:00 +0100

Alex Payne wrote:

If I had an iPad rather than a real computer as a kid, I’d never be a programmer today.

Sugar: The Bitter Truth

Thu, 28 Jan 2010 22:49:05 +0100

Brainwashed: Seven ways to reinvent yourself

Thu, 28 Jan 2010 00:37:15 +0100

A ChangeThis Manifesto by Seth Godin: Brainwashed: Seven Ways to Reinvent Yourself. Interesting. Also there is an interview between Merlin and Seth on 43 Folders.

Using a webhook to GET information

Wed, 27 Jan 2010 17:33:36 +0100

This week I’m working on an application that needs to get a list of email addresses from another application. It has the following requirements.

Requirement #1: Only HTTP+URL+HTML. No SOAP, SQL or other technologies.

Requirement #2: The list can’t be cached. It needs to be updated on the moment that the information is used.

Requirement #3: Just one URL.

Requirement #4: Authentication is very important. Only programs, that are authenticated can read this information.

Cool Websocket, Twitter and XFactor demo

Tue, 26 Jan 2010 13:47:37 +0100

Pushing the boundary of Real Time Web with Twitter and XFactor:

I am glad that I was able to show how exciting node.js and WebSockets are to make real time web application.

This is a really cool realtime web application demo. Watch the video.

Schwartzian transform in shell and vim

Tue, 26 Jan 2010 13:12:36 +0100

A few days ago I had to create list of email addresses sorted on the domainname. All addresses with the same name should clump together. Being a Perl programmer, I quickly wanted to write a Perl script to sort this list of data. Then I tought, why not use Vim to look at the intermediate steps and do it with filtering. The following is the result.

:%!perl -pe 'm/\@([-\w]+)\./; $_="$1\#$_";'
:%!sort
:%!cut -d\# -f2

The first line parsed the domain from the data and pastes it in front of the orignal, seperating it with a ‘#’. The second line obviously sorts the new list. The final line removes the domain that I put in front. This leaves a list of the originals.

Important message about HTML5 video codecs

Mon, 25 Jan 2010 14:57:23 +0100

This article takes a look at the history of the web to find out what we need to do about video codecs.

HTML5 video and H.264 – what history tells us and why we’re standing with the web.

Copying HTML from a webpage to Google Wave

Sun, 24 Jan 2010 21:19:07 +0100

It seems that I can copy formatted text (including urls) from a webpage to Google Wave and the formatting doesn’t change. This happened in Google Chrome.

Is this a Google Chrome feature? Or is this a Google Wave feature? Or is this jkust supposed to happen and did this already work a long time?

Giving URxvt a try again

Sun, 24 Jan 2010 20:51:48 +0100

It’s that time of year again. Some applications come and others go. This time it’s gnome-terminal that goes.

The thing with rxvt-unicode is that you need to configure it to be pretty. Luckely I found a page containing nice colors and settings.

At the moment I have only tried it for a few minutes, but I already like it. Let’s see how this goes.

The advantage microformats have over other formats

Sat, 23 Jan 2010 16:15:39 +0100

I just realized what the big advantage is, that microformats have over other formats.

I was working on implementing the vevent microformat in my social concert calender. This was really easy. All I had to do was add some classes and some tags in special formats (most notably the ISO8601 date format).

You could say that the big advantage of this is that I only have to change a bit of markup and that it’s really easy. But that is not the biggest advantage.

Perl 5.11.4 development release released

Fri, 22 Jan 2010 14:55:33 +0100

Perl 5.11.4 is released:

This is the fifth DEVELOPMENT release in the 5.11.x series leading to a stable release of Perl 5.12.0. You can find a list of high-profile changes in this release in the file perl5114delta.pod inside the distribution.

Perl web server

Fri, 22 Jan 2010 14:44:33 +0100

Plack is a Perl Web Server:

Plack is the superglue interface between perl web application frameworks and web servers, just like Perl is the duct tape of the internet.

This is interesting and maybe useful in my webshop platform.

Firefox 3.6 released

Fri, 22 Jan 2010 14:15:36 +0100

Firefox 3.6 released

If you’re a developer you should take a look at the Firefox 3.6 for developers page.

Find your local IP address in Linux

Mon, 18 Jan 2010 11:36:40 +0100

Today I created this simple script that will find your local IP address or you Linux machine.

#!/bin/sh
# Shows ip address of eth0
/sbin/ifconfig | awk '/^eth0/,/^$/' | awk '/inet addr/ { print $2 }' | cut -d: -f2

It uses the output of ifconfig. First it finds the part that contains the information for eth0. Then it find the line with the inet addr, which contains your IP address. At the end it cuts the line in two parts and only prints the second part.

Maybe you just don't want to switch

Sun, 10 Jan 2010 17:28:53 +0100

My hypothesis is that people who are comparing iPhone to Android, actually don’t want to switch. They have to find some problem, so they don’t have to.

And why should they switch? I don’t know. If you’re happy with your phone and the way it works, you shouldn’t switch. It seems they want the Android phone to be an iPhone. But it isn’t. And it shouldn’t try to be. It’s something different.

Reversing an arrayref is too hard

Tue, 05 Jan 2010 15:01:40 +0100

Let’s say I have this line of code

my $numbers = [ 1, 2, 3, 4, 5, 6 ];

and I want to reverse the items in the list. In Perl 5 there is this useful builtin function which does just that. There problem is, it only works on lists, not arrayrefs. If you use it on an arrayref, you will reverse the string representation of the arrayref. Which will return something like this:

The Most Applications?

Tue, 29 Dec 2009 11:09:12 +0100

When you read about people wanting to switch to an Android phone, they will say that the iPhone has the most applications. Last thing I heard about this was that the iPhone has about 100.000 applications and Android about 16.000 to 20.000. This is only a factor five. That one number is bigger than the other is obvious. But is that the best way to compare these two app stores?

Spreadsheet import

Sun, 27 Dec 2009 14:50:29 +0100

osfameron asked:

I’ve been prototyping ways for customers to import data into our system. […] How would you tackle this task? Is there even an elegant way to do it imperatively?

He is trying to import data into his system, but his information is not all in a flat structure. It looks like this:

Name        Price   Tag
Brie        2.00    Dairy
                    Cheese
                    Food
Chablis     5.00    Wine
                    Alcohol
                    Drink

As you can see the there is a start row and a few extra data rows after that.

People think I love computers

Wed, 23 Dec 2009 12:17:52 +0100

Ted Dziuba wrote:

People think I hate programming. Nope. What I hate is fording endless rivers of horseshit that are in the way of seemingly simple tasks. And I hate it even more when I have to explain to a non-programmer what I am doing, “building LXML against a different version of libiconv because I think it might be the source of a crash”.

Yes. The thing that I would say is this:

What? RSS is dead? Again?

Wed, 23 Dec 2009 11:54:34 +0100

Steve Rubel wrote:

The decade is coming to an end. And with it, so has the era of feeds too faded - though you can argue it never got off the ground. Even with real-time technologies like pubsubhubbub, RSS today feels slow and it’s clear its best days are behind it. Feed reading, like blogging, feels “very 2005.” I wasn’t convinced until recently, however.

You could say that I’m not convinced yet, either. Still I wouldn’t know what I would do without RSS.

Twitter, I don't care anymore

Wed, 23 Dec 2009 11:28:47 +0100

I have had an account with Twitter now, for almost three years. According to When did you join twitter?, I joined twitter over two years and nine months ago. Lately I’m wondering if it’s useful for anything. It’s a lousy news reader, it’s a terrible communication medium and the mechanics are all in one company.

There is no way for me to send messages to the people I would like to send messages. Let’s say this is the same group of people that I would send SMS messages to. These aren’t on Twitter and probably never will be. They tried it and left it, never to return. These are the kind of people that don’t have fancy phones, with fancy apps, that allow them to use Twitter in a useful way.

Skeptics vs. Scientists

Wed, 23 Dec 2009 10:33:21 +0100

If I read the title of this diagram correctly, it seems to imply that the skeptics aren’t scientists.

The Global Warming Sceptics vs. The Scientific Consensus

I don’t think this is that case.

Gruber on Flash

Tue, 22 Dec 2009 14:47:45 +0100

In Why the HTML5 ‘Video’ Element Is Effectively Unusable, Even in Browsers Which Support It John Gruber says:

I truly hope to see Flash fade as the de facto standard for embedded web video, and I’m willing to put my markup where my mouth is.

Me too, and also for everything else.

Why don't we build a software tower?

Thu, 03 Dec 2009 12:35:00 +0100

We should build towers of software instead of just replacing the platform every few years. Many client software programs are the end of the line. It’s not easy to build new software on top of those programs.

The problem with this is that this way client programs will become better, but it’s not possible to build on top of them.

Each program should have an API that allows other programs to build on top of them. There is a lot of functionality that is build in to programs, that could just as easy useful to other programs.

Use named capture buffers to fill a hash

Mon, 30 Nov 2009 14:53:08 +0100

This is a small Perl 5.10 tip. You can use named capture buffers to fill a hash. Before 5.10 you needed to ‘unpack’ the values from a regex match into a hash.

I will give a small example that shows the problem this creates.

my $str = "name=value";
my %result;

if ($str =~ m/(\w+)=(\w+)/) {
    $result{name} = $1;
    $result{value} = $2;
}

The problem with this is that you need to number the variables and assign each individually to the hash. In Perl 5.10 you can do the following.

I want a programmable everything

Mon, 30 Nov 2009 12:44:45 +0100

As a programmer I want a programmable world. The web has been a big step forward in making things programmable. Especially in the form of REST. HTTP clients can send HTTP requests to urls and proxy can filter or change what is passed through.

In the future more real world things will become programmable. For example I can program my domain name provider. As long as I supply enough money to them, I can register as many domain names as I like.

MMS photo sharing on Twitter

Tue, 17 Nov 2009 10:21:44 +0100

It seems it is now possible to share photos with MMS to Twitter. It’s interesting to notice that the people at Orange UK figured out that if let people send MMS messages to an interesting service you can make a lot of money.

I have never send an MMS in my life and I probably never will, but if the use is interesting or valuable enough, I just might.

The other important thing to notice is that Orange UK can (and probably will) save half of the money (and bandwidth) that would normally be needed to send a MMS. They only have to receive the MMS from their customer. To get the photo to Twitter they only need a few servers that call the API.

I can't imagine that I would write that code in the first place

Tue, 17 Nov 2009 09:33:21 +0100

I’m afraid that’s a failure of your imagination. – Rush, SG:U.

When I’m looking at code on Stackoverflow (or some other place with bad code), I’ll sometimes see people asking questions about pieces of code, that I can’t imagine I would have written like that in the first place.

Why is that? I just noticed it a few minutes ago, but it looks like I have to think about that some more…

Use Perl 5.10: _ prototype

Mon, 16 Nov 2009 21:17:22 +0100

This week I will show a simple example about how to use the underscore prototype which is new in Perl 5.10.

This feature was added to allow you to write functions that work like builtin functions. It’s up to you to not abuse it and write unreadable code, of course.

This example shows how to use this new feature. It allows you to use the $_ variable as an argument for a user defined function.

I don't know why I didn't make these aliases before

Tue, 10 Nov 2009 14:36:51 +0100

A few days ago I created two new aliases for places I connect to with ssh. Both locations have a three character alias now.

To use the aliases I created a new file called ~/.aliases. This file contains all the aliases I use. This file should be sourced in the ~/.bashrc file with the following command.

source ~/.aliases

Then add the following line to the ~/.aliases file.

alias realias='$EDITOR ~/.aliases; source ~/.aliases'

Restart bash and type realias. It will open an editor to the ~/.aliases file and source it when your done.

Whitespace at end of line

Mon, 09 Nov 2009 11:41:57 +0100

On Coding Horror Jeff wrote about whitespace at the end of lines of code. I hate that as much as the next guy. It seems irrational, but I think it’s not. It has no function and only creates problems on times when you don’t expect them, especially with source code control tools.

So I wrote a small piece of Vim script code to highlight the spaces at the end of the line in bright red.

Use Perl 5.10: Named capture buffers

Sun, 08 Nov 2009 20:46:48 +0100

In the latest version of Perl 5 the regex engine also got a big upgrade. There are many changes that made it faster and more correct for certain regexes. This time I will explain the new features called Named capture buffers.

Named capture buffers are similar to the numbered capture buffers, like $1 and $2. The named versions of these work the same except that you can give them a name like name or value. This will help you with documenting the regex that you use.

New keyboard, strange wrist support

Thu, 05 Nov 2009 11:29:34 +0100

I started using the Microsoft Natural Ergonomic Keyboard 4000 keyboard about two weeks ago. At first I didn’t use the strange wrist thing. It looks strange and lift my wrists a lot.

Today I attached the wrist support thing and at once my typing is becoming faster and better. It looks like that thing makes the angle better for typing the keys. I’ve only tried this for a few minutes know. I will try it a little longer to find out how this works. It seems nice enough.

Perfection

Mon, 26 Oct 2009 13:07:15 +0100

A person who says a thing has only advantages and no disadvantages, is either a fool, or a liar.

Bytecode interpreter

Mon, 26 Oct 2009 10:58:32 +0100

A bytecode interpreter is basically a loop and a lookup table. The interpreter starts at the beginning of an array of bytes. Each byte in this array is an index into the lookup table. For each key in this table there is a piece of code that needs to be executed. Code for that may look like this:

typedef unsigned char byte;

// the simplest program
byte program[] = {
    0,
};

byte* ip = program;                   // instruction pointer

while ((ip=(lookup_table[*ip])(ip))!=0) {
    // does nothing else, but could
}

The expression in the while loop is a bit complex, but we can divide it in parts. First there is ip. This is the instruction pointer. It points to the instruction that needs to be executed.

Use Perl 5.10: say

Sun, 25 Oct 2009 21:25:46 +0100

This is the first article in a series about new Perl 5.10 features. I’ll try to write one article each week, but you’ll never know.

This first article is about the new builtin function say. The say function is similar to print in how it works. Whenever you want to use say or other features from Perl 5.10, you need to declare that you want to use these features.

use 5.010;

After you have done that you can use the function like this.

Have you forgotten who you are?

Fri, 23 Oct 2009 16:13:05 +0200

In Makebelieve help, Old Butchers, and Figuring Out Who You Are (For Now) talks about how if you forget who you are, you’ll procrastinate; and thoughts about learning and play, mastery and old butchers and playing with the stuff you have lying around your desk. It’s a forty minute video, which with Merlin is always worth your while.

PubSubHubbub and polling?

Mon, 19 Oct 2009 11:51:42 +0200

Via PubHubSunday - Tim Bray:

On the other hand, Twitter clients which rely on polling seem to make their users happy. I see nothing in the spec about supporting polling, i.e. how a client might ask a hub for its version of a feed, but that seems to me like it might be a real useful function.

I don’t think that adding polling to PubSubHubbub (PuSH) would be a good idea. Removing the need to poll from feeds is one of the reasons for its existence.

Seth Godin: Quieting the Lizard Brain

Thu, 15 Oct 2009 21:43:12 +0200

Seth Godin: Quieting the Lizard Brain from 99% on Vimeo.

Shipping is more important than creativity.

Autocomplete contexts and people with GTD in Vimoutliner

Thu, 15 Oct 2009 14:15:54 +0200

I wrote an article about GTD and Vimoutliner. This post adds a few simple things you can do to simplify your edits to the todo.otl file.

In Vim it is easy to autocomplete a word or line. You can complete a word by typing the first few characters of the word you want to complete. Then type CTRL-N to complete the word. You can try other words by typing CTRL-N more often. This will try to complete your word with a word that can be found in the same file.

Interview with Sir Tim Berners-Lee

Tue, 13 Oct 2009 22:08:14 +0200

Search options in Google

Tue, 13 Oct 2009 15:37:16 +0200

I like this, but too bad it doesn’t work in the Dutch search engine, yet.

Debian upgrade to Lenny completed

Tue, 06 Oct 2009 12:36:06 +0200

I upgraded my webserver to Debian Lenny last night. It went almost without problems. This was because I followed the release notes. This helped a whole lot.

Still this morning there was a small problem that I didn’t notice yesterday. I didn’t receive any email. So I took a look in the exim4 mainlog at /var/log/exim4/mainlog. It contained the following message:

lowest numbered MX record points to local host: servername

All messages that should be delivered in a local mailbox were frozen. The solution was actually quite simple. First I needed to change one line in a config file. It contained something that looked like: DEBCONFxxxDEBCONF. This is a line that would normally be replaced by the update-exim4.conf script. But that doesn’t work anymore.

Perl 5.11.0 released

Mon, 05 Oct 2009 17:14:37 +0200

Jesse Vincent released a new development version of Perl 5:

It gives me great pleasure to announce the release of Perl 5.11.0.

Perl 5.11.0 is a DEVELOPMENT release. We’re making it available to you today to make it easy for you to test your software on what will eventually become Perl 5.12.

The nice thing about this release is that there will be releases of Perl every month, with the dates already scheduled. The next release (5.11.1) is coming on October 20.

Upgrading to Debian Lenny

Mon, 05 Oct 2009 16:57:22 +0200

One month ago Debian released a new version of their operating system. The new version is called Lenny. These release notes contain a list of things you need to do to upgrade without problems.

This afternoon I upgraded a virtual machine image and tonight I will upgrade my server. By doing it this way I found a few problems I will have that I can fix then or before they will happen.

Ubuntu Update Manager as a notification icon

Fri, 25 Sep 2009 17:39:45 +0200

I really don’t like that the Ubuntu update-manager opens a window when it finds that there updates that can be installed. In older versions Ubuntu showed a small icon in the top panel.

Apparently Ubuntu still allows you to do that, but you will need to call the following command:

gconftool -s --type bool /apps/update-notifier/auto_launch false

This will not add the icon to the top panel directly. You will need to wait for the next update for that.

Programming notebook

Mon, 21 Sep 2009 14:11:53 +0200

Using a small notebook or legal pad helps me to focus on the problem at hand. If I notice a problem or bug, that I don’t have to fix to solve the current problem, I will write it down on the list of todo items for the program.

The other nice thing about writing down a todo list this way, is that it will grow and shrink over time. At the end of the day I have two lists: one with the things that I did that day, and one list with the things that I can work on the next time.

My explanation of WebHooks

Wed, 26 Aug 2009 16:03:43 +0200

HTTP requests are send by clients to servers. Most of the time the client is a webbrowser. The only thing that WebHooks says is this: servers are clients, too.

WebHooks have nothing to do with realtime updates or with sending HTTP requests to browsers. It’s about servers sending HTTP requests to other servers when something happens.

Use ssh as a SOCKS proxy

Fri, 14 Aug 2009 13:49:25 +0200

At the moment I work from another place than home and sometimes I need to get on the internal network. Normally you would VPN for that kind of thing. But if your not scared to use SSH then it’s not that hard.

First you need to open a connection to your internal network.

ssh -D 9000 hostname

The -D 9000 option will open a port and create SOCKS proxy on your local machine. This allows you to send traffic to the internal network through the SSH connection. Replace hostname with the name of the host you want to connect to.

TinyThread GreaseMonkey script is not needed anymore

Thu, 13 Aug 2009 12:46:36 +0200

My GreaseMonkey script for TinyThread is not very useful anymore. The design has been changed to look a bit nicer. It’s good to see the changes were mostly functional.

This also means you can remove the GreaseMonkey script from your browser.

TinyThread with a bit of style

Wed, 12 Aug 2009 15:26:00 +0200

TinyThread is a simple website that will make it easier to have a conversation. You can login using OAuth with your Twitter account. When you start or join a conversation it will send a tweet to your followers so they can see where you’re talking about.

But TinyThread is a simple website with simple styles. That’s why I created a small GreaseMonkey script that adds a little bit of style to the thread page.

Facebook acquires FriendFeed

Mon, 10 Aug 2009 22:15:17 +0200

I’m not sure what to say. FriendFeed is an amazing service for sharing and commenting on stuff. And now they are acquired by Facebook. I’m not sure what will become of this. But it doesn’t feel good.

Vim function to replace many spaces with one

Wed, 05 Aug 2009 11:33:36 +0200

At last I have found the function that will replace many spaces with one space. I first wrote a blog post about this in januari of 2007. Then I wrote a blog post about how to enhance this function to move the cursor one position after the inserted space. With an update a day after that, which said that it didn’t work in some instances.

Today I’m proud to announce the final and working function that works as it should.

Programming pattern: Temporary data

Tue, 04 Aug 2009 15:19:13 +0200

Temporary data is a simple pattern that I use while I’m trying to get some code working. The inverse of Temporary data is that you get the data, for example, from a database.

The code you have to write to get the data from the database is often many times as long as the code you need to specify the data structure.

my $languages = [
    { code => 'nl', name => 'Nederlands' },
    { code => 'en', name => 'English' },
];

If you would like to get this same data structure from your database you have to do a lot of work before this works. You need to design and create a table, fill the table with example data and write code to retrieve the values from that table.

Vimoutliner links

Mon, 03 Aug 2009 15:17:56 +0200

Today I will post some links to other pages that talk about Vim outliner.

Potatoes from my garden

Sun, 02 Aug 2009 18:14:30 +0200

The potatoes are ready now.

Nginx and gzip

Sat, 01 Aug 2009 12:58:50 +0200

I was trying to find some ways to increase the speed of my webshops, because speed matters.

I did this by using the YSlow Firebug add-on. It told me that I didn’t gzip some of my static files. That seemed strange to me because I already enabled gzipping in my nginx.conf.

I used curl and Firefox to find out if my files where gzipped. It seemed they weren’t. So I changed my gzip settings in nginx.conf to the following on my development server. (Source).

Switch from Hotmail to Gmail

Fri, 31 Jul 2009 13:28:23 +0200

Since a few months you are able to move from Hotmail to Gmail. The biggest problem was that you couldn’t take you old emails with you to Gmail.

The other big problem was that you have to everybody about your new email address. Switching has a big cost. The way this works is that you don’t have change your email address, because even the new emails that arrive after you move will come into your new Gmail inbox.

Insert the current date and keep it up to date

Tue, 28 Jul 2009 14:22:38 +0200

You would like to add an automatically updated timestamp in your text files. You can do that by adding 6 lines of code to your .vimrc.

The following command will call the function LastMod() whenever a buffer of file is written.

autocmd BufWritePre,FileWritePre *.html   call LastMod()

The following function will find all files containing ‘Last modified:’ and replace them with the current date and time.

fun LastMod()
  exe "%g/Last modified: /s/Last modified: .*/Last modified: " . strftime("%Y-%m-%d %T")
endfun

The biggest problem with this function is that using the :substitute function will move the cursor to the beginning of the line. This will even happen when nothing gets replaced. This is extremely annoying.

How to use Vimoutliner checkboxes

Mon, 27 Jul 2009 16:41:16 +0200

Vim outliner is an outliner tool. As the name implies you can write outlines with it, but with this particular one you can also create todo lists. A todo list can be created without much effort.

First open your todo file, todo.otl for example. By using the otl extension, Vim outliner will be loaded automatically.

Next, type a task you have to do in the future. This could something like write blog post about Vim outliner. Remember, because this is Vim, you have to type i to start insert mode.

Words are tags, too

Fri, 03 Jul 2009 10:41:47 +0200

Why don’t we use words as tags? Search engines already know that words are tags. Why do we need to put an extra character (#) in front of a word to make it special? Here are two reasons I can think of.

The first reason is, that by using an extra character a website can make a link from the word that links to a search page or a special page for the tag. The problem is that if the post wasn’t tagged then there would be no link. How can you find words that weren’t tagged with the character? You would need an extra search interface for those words. But if you have that search interface you don’t need to tag posts in the first place. Every word is a tag.

A commandline script for Twitter

Tue, 02 Jun 2009 20:50:06 +0200

This is the script that I use with Vim to send my Twitter updates.

In Vim you can use it by typing

!!perl twitter.pl

If you then type Enter it will send the current line to Twitter.

You do need to install Net::Twitter and its dependencies.

Write Twitter drafts in Vim

Fri, 29 May 2009 15:01:39 +0200

Not everyone writes drafts for his Twitter posts. It seems silly even to do this.

But for the people who don’t think writing drafts is silly (and use Vim), I wrote a few lines of Vim script that will help them keep their lines just short enough.

Put these lines in your .vimrc file and start writing. You should change the filename to the name of the file that you write your drafts in. As usual, this code comes without any warranty.

HTML5 and video possibilities

Fri, 29 May 2009 14:07:53 +0200

These days many videos are published to the internet by people using cellphones. Many of these videos have crappy sound, because of how these cameras are built and the way these cameras are used.

The microphones are not at the best place for recording the sound and because the volume is too low, there is much background noise, because the volume needs to be increased.

With the Flash player based videos we are dependent on Adobe (for Flash), the video owner or the video website too give us content or technology that lets us improve the video.

Notes on how blogging should work (for me)

Mon, 25 May 2009 16:47:50 +0200

Sometimes I have the following ideas about blogging and other writing for the web. The thing is that these ideas will not apply in the same way to other people. I think some of the points can be generalized for other people and applications.

Notes

These blog posts on this website are written with Vim and a few scripts through a SSH connection to my server.
I would like to use Vim to edit my blog posts.

Spam on Twitter

Tue, 12 May 2009 10:54:00 +0200

A few months ago I said that it’s not possible to spam Twitter. This is because you can choose who you follow. And people can’t send messages to you if you don’t follow them. This makes Twitter unspammable.

The above is still true, with the exception that with search.twitter.com people will find messages of people that they don’t follow. This problems becomes bigger when people will start searching for their @usernames. If someone now tweets with a message containing your username it will appear in your client.

My first vegetable garden

Fri, 08 May 2009 11:26:39 +0200

I planted my first vegetables today in the garden. Eight potatoes.

Use MySQL Fulltext for search on your website

Fri, 10 Apr 2009 12:22:13 +0200

This week I have been working on a search engine for my webshop platform. And while a big part of this work is on the layout of the result page, I also have to work on the backend.

The backend that I built is using MySQL fulltext indexing. The default MySQL was not optimal for my goals. Some queries don’t return any results. This can can fixed by changing a few config variables in my.cnf.

Logging HTTP requests with Apache

Wed, 01 Apr 2009 13:20:09 +0200

I created two simple mod_perl handlers, that help me find the response time of my web application. See it on github apache2-logging-handler.

The code is so simple that you can recreate them easily yourself. Note the use of the pnotes function.

$r->pnotes('start_time');

With pnotes you can share information between handlers. I had to search for a bit and this works great.

Simple Beanstalkd example

Sun, 29 Mar 2009 20:07:11 +0200

According to its website, Beanstalkd is a fast, distributed, in-memory workqueue service. In simpler terms this means clients can add tasks to a queue and workers will execute these tasks whenever they have time.

I will show how this works using the perl client libraries. The Beanstalk::Client libraries can be found on the CPAN.

Both the clients and the workers use the same library. The following example will put a ‘print’ task to the queue.

Try and experiment

Mon, 23 Feb 2009 14:10:43 +0100

When I am programming I will try things out. When I don’t know if or how a feature of a programming language works, the way to find out is just trying it. The nice thing about computers and programming languages is that they won’t work or will complain, when something isn’t the way they expect it.

For Trying and experimenting to work, you’ll need two things: feedback and reasoning skills. I could write here that you also need creativity, but I can’t write anything useful about that yet.

Creating stopmotion videos with mencoder

Tue, 03 Feb 2009 22:58:04 +0100

A few days ago I found out that my camera can make little stopmotion movies. It’s really easy, but the quality is really low, only 320x200. My camera can make pictures at a resolution of 2560x1920 and I want to make use of the available pixels. So I start my search for the most amazing way to create a stopmotion movie.

The first method of putting pictures after each other to create a stopmotion movie I remembered was animate, a program bundled with ImageMagick. When I tried to use it on the 2.5MB pictures, it took a lot of time. After I resized the pictures to 800x600 it created the animation in a few seconds. But it was not exactly what I was looking for.

I'm creating something every day

Wed, 28 Jan 2009 23:56:14 +0100

Today was the fifth day that I created something for my Create something every day project. It’s going well. I created something each day. A few days I even created more things. If you would like to know what’s going on here please check out the website.

Creating something every day is about creativity and about failure. When you have create something every day, you have a lot of opportunities to fail. Failure in the sense that I created something that wasn’t really good. Because even when it’s bad, it will go on the website. This way I don’t have to care about perfection. Only about production and practice.

DIY steadycam

Thu, 15 Jan 2009 21:45:18 +0100

I started building my own DIY steadycam. I based it on this video.

DIY Steadicam - Flying Camera Support from Videopia on Vimeo.

The first part only took me a few minutes to build. It looks like this.

Do what you love

Sun, 11 Jan 2009 13:10:27 +0100

I’m a happy boy. Do what you love. It’s important.

Steak and strippers

Thu, 08 Jan 2009 14:30:35 +0100

A presentation about working as a programmer in a corporation, how to build to your own stuff and doing things that you love.

Zed Shaw - The ACL is Dead from CUSEC on Vimeo.

The Vimeo page has more information.

Via: blog.cusec.net

Making a movie

Tue, 06 Jan 2009 12:46:39 +0100

This year I’m going to make a movie. People will wonder: “Why are you going to make a movie? You’re a software developer. You don’t know anything about filmmaking.” They would be right. I don’t care. And I will learn something in the process.

I think we live in an amazing time for creating beautiful stuff. Cameras aren’t that expensive. Maybe someone has a camera lying around somewhere. Distributing the video on the internet isn’t very hard.

Ten million music tracks remain unsold online

Wed, 24 Dec 2008 15:15:29 +0100

According to this article in the Daily Mail, it seems that there are a lot of songs, that weren’t sold at least once. It says that the Long Tail theory of Chris Anderson predicts that about 80% of the songs should account for about 20% of the sales.

But just saying that it should work like this, doesn’t make it so. For the Long Tail to work it should be easy to find, link to and buy songs that are not in the bestseller lists. If it’s not easy to find a song, it won’t be sold. If you can’t link to a song, it won’t be sold. If you can’t listen to a song, it won’t be sold. If you can’t buy a song (for a reasonable price, in a reasonable way), it won’t be sold. It should be easy to talk about and point people to those undiscovered songs.

Pownce and Sandy both stopped

Tue, 23 Dec 2008 20:46:59 +0100

It seems I started using Pownce and I want Sandy in the same month. Now they both stop about a year later.

Now I have to say I didn’t use both services much, so it’s not really a big problem, but still.

I liked that Sandy would remind me every two weeks to respond to the woningzoeker and help me find a new home. I think this weekend was the last time. Maybe something or someone else can help remind me of this.

Finding a better non-linear video editing program

Tue, 23 Dec 2008 16:34:07 +0100

First I thought there weren’t any video editing programs for Linux. After a bit of searching I found a few. But somehow non of these worked for me. Some are unstable and crash, others are unusable. I still do like to edit some videos on my Linux box. And as it seems I’ve started a company a few weeks ago. So maybe my next product will be a video editing program.

The new Ubuntu 8.10

Mon, 03 Nov 2008 00:33:35 +0100

I installed the new Ubuntu 8.10 on friday. The thing is I have no idea what the differences with the previous version are. So let’s take a look at the release notes and changelogs.

According to the changelog this new version of Ubuntu uses the new Gnome 2.24. The release notes of Gnome explain some of the new features.

The version of Gimp is also updated to 2.6. This new version of Gimp has changed a whole lot. Release notes are here.

New monitor

Sun, 12 Oct 2008 17:40:49 +0200

Yesterday I bought a new monitor, the Samsung SyncMaster 2493HM. Before this I owned a 19" monitor, which became a bit to small. This new one is 24" an uses a resolution of 1920x1200, which is huge.

At the moment I only have one problem with the monitor and that is the menu. When it is a bit dark in my room, I need a flashlight to see where the buttons are. The other problem is that the buttons are touch sensitive not tactile. The only response that you will get from the buttons is the menu on the screen.

Fiddle - a music player

Mon, 15 Sep 2008 16:34:50 +0200

All music players suck, all in different ways. The music player that I created sucks too. A lot actually, but that’s to be expected.

The work of three days is now available to the public in some kind of alpha release. The player is called Fiddle and is available in my Git repository. But please take a look at the website that I created for it. It contains a lot of good information about downloading and running Fiddle.

A hovering statusbar

Sun, 07 Sep 2008 00:51:29 +0200

I created a Greasemonkey script that will show a hovering statusbar when hovering over a link. It looks like this:

Use at your own risk! This script comes with no warranty. You have been warned.

Install the script: Hovering statusbar Greasemonkey userscript

jQuery and postJSON

Fri, 05 Sep 2008 23:52:56 +0200

The last few days I’ve been using jQuery to write some REST based javascript and HTML. While I was doing that I needed a function that looked like getJSON, that did a POST instead of a GET. The difference is that I send a bit of JSON and receive a bit of JSON, instead of sending form-like data. So I created the following bit of code:

$.postJSON = function (url, data, callback) {
    $.ajax({
        'url': url,
        'type': 'post',
        'processData': false,
        'data': JSON.stringify(data),
        contentType: 'application/json',
        success: callback,
    });
};

If you know jQuery a bit, you will know that this sends an Ajax request to url. Later when I used this code to do a POST a followed by a GET, I didn’t receive the thing that I wanted: a Javascript object. I did however get a string that looked like one. That confused me for a bit. Then I remembered a FAQ or a weblog post about another implementation of postJSON, that was written like this.

Using ack to check coding conventions

Sat, 30 Aug 2008 16:47:19 +0200

Do you know Ack? It's a grep-like program. That uses perl regular expressions instead of the normal Posix ones. You can find it on the CPAN.

The following Ack call will check your perl code for problem with a space missing behind a controlstatement keyword.

ack --perl '(?\@<!\w)(if|while|elsif|return)('

If you use Vim you can also use the following piece of vimscript in your .vimrc file:

highlight WHITE_ON_RED ctermfg=white ctermbg=red

function! BadNonInvocations ()
    2match WHITE_ON_RED /\w\@<!(if\|elsif\|while\|return\|for)(/
endfunction
call BadNonInvocations()

Human readable date in vim outliner calender

Mon, 18 Aug 2008 16:01:25 +0200

I created a small Perl program to convert relative dates to absolute dates in the format that I use for my calendar. My current calendar file looks like this.

If I want to add a date and I don’t know the actual numbers, I can use the following program to convert the date. It will also respect the whitespace in front of the text.

Programs that I use in 2008

Fri, 08 Aug 2008 18:01:11 +0200

In 2005 I wrote a small post about the programs that I use on a regular basis. I will try and find out what has changed and what stayed the same.

I still use:

vim - an editor
rxvt-unicode - an X terminal
ion3 - a window manager
xmonad - another window manager (written in Haskell)
firefox - a web browser
mutt - a email client
vim outliner - a todo list/outliner tool

Programs that I don’t use anymore:

I released a HTML parser

Wed, 06 Aug 2008 18:52:14 +0200

I created a HTML parser written in C++. It’s based on the HTML5 specification. The code can be downloaded with git:

git clone http://code.peterstuifzand.nl/git/htmlparser.git/

or:

http://code.peterstuifzand.nl/cgi-bin/gitweb.cgi

I use this HTML parser in a internal searchengine. It parsed everything the spider could find.

If you like to use this parser, look for the Parser class. This class expects an Emitter object. This can be a ListEmitter or a subclass of Emitter. I wrote a simple Emitter that finds all <a href=""> tags and inserts them into a MySQL table.

I released a small C++ utility library

Tue, 05 Aug 2008 22:48:00 +0200

I just released a small C++ utility library. At the moment it contains three modules: an URL class, a config file reader, and a testing framework.

The code can be found at http://code.peterstuifzand.nl/cgi-bin/gitweb.cgi

or use git to clone the project:

git clone http://code.peterstuifzand.nl/git/cpputil.git

The URL class is used in a search engine that I am currently writing. The code doesn’t do much more than I need at the moment. I want to make this code better.

Ternary operator

Sun, 20 Jul 2008 00:18:07 +0200

The ternary operator can be found in many programming languages. In some popular ones it is written as bool ? expr1 : expr2, which will evaluate to expr1 if bool is true or expr2 if bool is false.

The nice thing about the ternary operator is that one can write an otherwise big if block in one line. For example:

$var = null;
if ($x > 10) {
    $var = 102;
}
else {
    $var = 1044;
}

becomes

Batman

Fri, 18 Jul 2008 22:38:47 +0200

The last few days I saw a few things related to Batman. This is, of course, because the new Batman film came out a few days ago (in the US, in the Netherlands we still have to wait a few days).

A review of Dark Knight by the guys of The Totally Rad Show.

A review of some Batman comics by the guys of iFanboy.

I went to the NEMO

Thu, 17 Jul 2008 00:08:29 +0200

Monday my girlfriend and I went to the NEMO science center in Amsterdam. It is a place where you can discover technical and scientific things. From DNA to love and electricity to water.

NEMO is a five story building that looks like a huge boat. At the moment you have to go through a back entrance. There is a lot of construction going on at the moment.

Safe output

Sat, 05 Jul 2008 01:14:56 +0200

This is an article that I wrote about two years ago. I like to share it with you because I think that it contains a few nice rules for writing better software.

When creating websites, there is a time when you want to put some dynamically generated output to the web browser. With a CGI script this is done by printing to stdout. When you don't take some simple precautions it will be easy for crackers to take over your website.

My weblog supports comments, at last

Sat, 05 Jul 2008 01:04:05 +0200

Tonight I implemented comments on my weblog. I have this blog already for four years and now at last you can post a comment.

The biggest problem with implementing comments is that my blog is static. Otherwise it wouldn’t be that hard to implement the comments.

At the moment you shouldn’t pay much attention to the esthetics.

Radiohead Nude remix with old hardware

Wed, 11 Jun 2008 12:37:42 +0200

Big Ideas (don’t get any) from James Houston on Vimeo

Een reis weblog

Mon, 09 Jun 2008 18:12:20 +0200

Ik ben met een reis weblog begonnen. Het staat in http://peterstuifzand.nl/opreis/. Het kan zijn dat ik er in de komende dagen nog iets aan doe, qua ontwerp. Op dit moment heb ik daar nog geen zin in.

Het idee is dat ik daar tijdens mijn reis daar dingen op zet die ik meemaak. Dus neem een kijkje en plaats af een toe een reactie. Dat zou ik wel leuk vinden.

Adobe has plan for opening up Flash file-format specification

Tue, 03 Jun 2008 17:39:39 +0200

It seems Adobe will publish the Flash file-format specification. Maybe now we will get a good and open Flash player on non-i386 Linux systems.

The specification for SWF is available on the SWF Technology Center

I started using Friendfeed

Sat, 24 May 2008 15:43:03 +0200

I started using Friendfeed. I’m not sure about the functionality that it offers. I added a lot of services that I’m using on the internet. Now FriendFeed will collect all the different things that I do and write and create a new ‘feed’ of these. This can be an real feed or a page which shows all the items.

My feed can be found at http://friendfeed.com/pstuifzand. So if you are interested in what I’m doing, feel free to take a look at my feed.

In defense of food

Tue, 20 May 2008 17:46:15 +0200

Two interesting videos by Michael Pollan. The first one is about “In Defense of Food”.

The second one is really interesting about how to view the world from a plants eye view.

They’re both interesting and could change the way you view the world.

Link to this book:

In Defense of Food
Michael Pollan

First try Haskell web applications

Thu, 15 May 2008 15:56:28 +0200

I’m trying Haskell for writing Web applications. It should be really easy, but at the moment I’m missing the examples. The documentation doesn’t really help for generating the XHtml.

The following bit of code is something that I found: Haskell and Web applications. The article contains a simple example. I changed the code in the example to use a table instead of the spans. This turned out to be really easy to do.

Most used commands

Wed, 16 Apr 2008 19:52:21 +0200

The command to find the list of commands that you use the most is:

history | awk '{print $2}' | sort | uniq -c | sort -rn | head

I like this version because it has uses a few simple and useful commands.

My list:

11398 ls
 6724 cd
 5200 vim
 2330 sudo
 1462 mutt
 1131 perl
 1122 mplayer
 1036 svk
  825 mpc
  795 lt

The lt command is a shell alias for ls -lt. Other people don’t have a editor in this list. This probably occurs because they use emacs which works better when it is open a long time. I use vim that way sometimes, but most of the time I use it for small and fast changes.

Big error in my regex code

Thu, 10 Apr 2008 20:37:04 +0200

When I first posted the simple regex code I thought that it contained no errors. But when I tried it a few days after that with a few simple testcases (which I hadn’t considered in the test code) it failed.

ok $ match "world$" "world"
ok $ match "world$" " world"
ok $ match "world"  "hello world"

The first testcase worked. The other two didn’t, but they should have. After a bit of inspection with the trace function in Debug.Trace I found out that the function couldn’t move past the first character. I thought matchhere would take care of that, but it didn’t.

Interview with Richard Feynman from 1981

Tue, 18 Mar 2008 11:11:15 +0100

Playlist of all six parts of his interview from 1981.

Interesting video by James Randi and his million dollar prize

Tue, 11 Mar 2008 16:06:02 +0100

James Randi is among other things, a psychic investigator. Very interesting.

A new Gnome Do tutorial

Fri, 07 Mar 2008 16:32:20 +0100

Christer over on Ubuntu Tutorials wrote a tutorial about installing Do plugins. Also take a look at his other tutorial about installing Gnome Do.

And if you haven’t tried Gnome Do yet, please give it a try.

Simple Haskell regex program

Wed, 05 Mar 2008 15:47:04 +0100

I wrote a small piece of code to match a regex to a string in Haskell. The code is based on the example from Beautiful code.

match                       :: String -> String -> Bool
match ('^':reg) s           = matchhere reg s
match reg s@(x:xs)          = if matchhere reg s
                                then True
                                else matchhere reg xs

matchhere                   :: String -> String -> Bool
matchhere []         _      = True
matchhere ('$':[])   []     = True
matchhere (x:'*':xs) s      = matchstar x xs s
matchhere (r:rs)     (x:xs) | r == x    = matchhere rs xs
                            | r == '.'  = matchhere rs xs
                            | otherwise = False

matchstar                   :: Char -> String -> String -> Bool
matchstar c []  []          = True
matchstar c _   []          = False
matchstar c reg (x:xs)      = matchhere reg xs
                              || ((c == '.' || c == x) && matchstar c reg xs)

The matchstar function in this example is non-greedy, because it will try to match the character after * before it tries to match the star.

Haskell and XMonad

Tue, 04 Mar 2008 09:19:18 +0100

In my quest to learn Haskell I come across XMonad, a tiling window manager. At home I already use Pekwm. On my laptop I use XMonad now. To configure it I have to use Haskell, so that helps.

After sometime using Haskell, I looks like I get a hang of it. I tried it a bit before, but now I really start to get a hang of it. If you want to learn Haskell to take a look at A Taste of Haskell a video/presentation by Simon Peyton Jones in two parts.

Gnome Do has a new repository

Wed, 20 Feb 2008 12:08:58 +0100

Everyone that uses Gnome Do should update their package repositories, because there is a new version available.

Please take a look at the installation instructions for more information about the installation.

Gnome plugins in Launchpad bzr

Fri, 15 Feb 2008 13:55:26 +0100

I created a branch in Launchpad for my Gnome Do plugins. This to help development with other people, who are already on Launchpad.

So if you’re using Gnome Do please make a branch of my plugins and compile, test and use them.

Creating a branch is easy in bzr, just do:

bzr branch http://bazaar.launchpad.net/~peter-stuifzand/gc/do-plugins-ps

You now have a working branch. Use make and make install to start using these plugins. If you don’t want to use all plugins, just use make install from the directories that you would like to use.

Gnome Do plugins status

Wed, 06 Feb 2008 12:45:14 +0100

I now have a page that contains the status of my Gnome Do plugins.

Gnome Do plugin for connecting to SSH

Sun, 03 Feb 2008 16:56:32 +0100

I created a plugin for connecting to SSH with Gnome Do.

To use the plugin type ‘con ssh’ followed by TAB. Then type the name of the server you want to connect to followed by Enter.

Update February, 4 2008: The SSH plugin will now also list all hostnames that are specified in your .ssh/config.

If you installed the previous version please remove the ‘SSHAction.dll’ file from you .do/plugins directory.

MySmartUSB Linux programmer control tool

Thu, 31 Jan 2008 15:39:05 +0100

The MySmartUSB documentation contains a paragraph about a protocol for sending commands to the programmer. I wrote a small perl script that can send these commands.

The file: mysmartusb. It requires Device::SerialPort, which is a perl module that’s available on CPAN.

Or you could get the git repository from http://code.peterstuifzand.nl/git/mysmartusb.git with the command:

git clone http://code.peterstuifzand.nl/git/mysmartusb.git/

Blinking Led video and source code

Thu, 31 Jan 2008 15:28:39 +0100

This is my first microcontroller project video.

I deleted my Myspace and Friendster account

Thu, 31 Jan 2008 11:08:19 +0100

Yesterday was Delete your Myspace account day. I don’t use any of those social networking sites and therefore I deleted all of the sites that were left. I cancelled my Facebook account a few weeks after using it for a few weeks.

Social networking sites are flawed, but maybe someday we will find out a way to make this work, but it is not today.

If people want to communicate with each other they can use email, IRC, phone, IM or any other way. It’s not needed to have another system for those things. Friendships are somethingthat can’t be described in a simplistic database.

I programmed my first attiny2313

Wed, 30 Jan 2008 15:56:02 +0100

I programmed my first Atmel ATTiny2313 today. Of course this was a blinking led program.

I used the following code:

#define F_CPU 8000000UL
#include <avr/io.h>
#include <util/delay.h>

int main(void) {
    DDRB |= 1<<PB0; /* set PB0 to output */
    while(1) {
        PORTB &= ~(1<<PB0); /* LED on */
        _delay_ms(100);
        PORTB |= 1<<PB0; /* LED off */
        _delay_ms(900);
    }
    return 0;
}

This will blink a led if it’s connected to PB0 (or pin 12 on the microcontroller).

Sound is working

Wed, 30 Jan 2008 12:30:42 +0100

My laptop (a Toshiba Sattelite Pro L40) has working sound now! It started woking after I added the following two lines to the file /etc/modprobe.d/alsa-base

options snd-card-0 index=0 model=3stack options snd-hda-intel index=0 model=3stack

The problem was that the audio was working when I first started the laptop, but it would stop when I used the volume mixer. Changing the volume did something that made the audio stop working.

I really like Git

Wed, 30 Jan 2008 10:03:05 +0100

I have to say, I really like git. I like it almost so much that I switched to Linux for it on my laptop. I have two projects of mine in a git repository and it seems to work great.

I installed Ubuntu on my laptop

Wed, 30 Jan 2008 09:59:57 +0100

I have installed Ubuntu Linux on my laptop. This is the second time that I tried installing linux on my laptop. The first time there were all kinds of problems with unsupported hardware.

When I installed Ubuntu yesterday, everything worked (except for Wireless). After a bit of searching I found a solution in ndiswrapper. I’m not that happy with this, because it is using Windows drivers. I’m waiting for the release of the new madwifi wireless drivers, which I hope will fix this problem.

Vim: Just once space revisited

Thu, 24 Jan 2008 12:14:27 +0100

At the beginning of last year I wrote a weblog entry about how to write a function that removes all space but one in Vim. It didn’t work like I wanted, but now it does.

function JustOneSpace()
    " replace all whitespace around the cursor with a space
    s/\s*\%#\s*/ /e
    " search backwards for a space
    call search(' ', 'be')
    " move to the first character after the space
    normal l
endfunction

nmap <space> :call JustOneSpace()<cr>

I added the call to the search() function to move to the space that was substituted. All this time I wanted to fix this function by using regexes or special vim variables. I couldn’t find these. This is quite obvious, but it didn’t come to mind at first.

Graphical Disk Representation

Mon, 21 Jan 2008 20:52:39 +0100

This weekend I tried Gnome on Debian unstable to see how the compiz window manager and other new stuff was working. I’m currently use pekwm. After a few hours of usage, I reverted back to my current desktop.

On the way I found out a two things:

You should remove the package files that are downloaded by aptitude. I collected about 7 GB of .deb packages. You can clean this up by using the command: apt-get autoclean.
Gnome contains a nice Graphics Disk Usage Analyzer called baobab. It shows the amount of diskspace a file or directory uses in a graphical representation.

Using R with visitor data

Mon, 21 Jan 2008 17:19:46 +0100

R is a statistics program. I can calculate statistical functions and draw nice graphs. Today I used it for showing some graphs.

I use R on my linux system, but it also works on Windows. To install it look at website of R.

Data from a file can be read with the function read.table(filename), where filename is the name of filename that you want to read. This would look like:

visitors <- read.table('visitors.dat')

The visitors.dat should contains two columns like this:

Weekend projects podcast

Tue, 15 Jan 2008 13:07:22 +0100

This is a video podecast that I watch regularly by Bre Pettis. The Weekend projects podcast shows a project you can make over the weekend. It’s very inspiring. When you haven’t seen it already, you should take a look at the archive.

Art and electronics project

Fri, 11 Jan 2008 01:24:14 +0100

A few weeks ago I created an art project together with my girlfriend involving video and electronics. I created the electronics part for her.

The technical part of the project was based on a simple idea. When someone walks by it should play a short piece of video.

The sensor

I made a sensor that notices changes in the light received. The idea is that when someone walks by the light falling on the LDR changes. The resistance of the LDR changes when the light changes. The change in resistance can be found out by measuring the voltage over the LDR.

My website is on a new server

Wed, 09 Jan 2008 17:17:47 +0100

In the last few weeks I have moved a part of my websites to my new server. This is now and actual server, not a computer hidden behind an ADSL router. I’m curious to find out how this actually works.

My Pownce profile

Wed, 28 Nov 2007 09:16:54 +0100

Maybe I should link to my Pownce profile.

Pownce

Tue, 27 Nov 2007 11:48:38 +0100

I just received my Pownce invitation. Now let’s see what this is.

The next book I'm going to read

Mon, 26 Nov 2007 15:59:49 +0100

I just got Mastering Regular Expressions by Jeffrey Friedl. I already know Regular Expressions and I think that I’m pretty good at them. Still I will read this and I think I will get something out of this. Maybe a deeper understanding of regular expressions.

Jeffrey E.F. Friedl" />
Mastering Regular Expressions
Jeffrey E.F. Friedl

Kindle: ebook reader

Wed, 21 Nov 2007 10:48:40 +0100

Amazon released an ebook reader: Kindle.

Please read: The Future of Reading and DUM.

I want Sandy

Thu, 15 Nov 2007 12:04:14 +0100

I want Sandy is a personal assistant, who will remind and remember all things you send to here via email.

Write paragraphs like:

remind me to take out the garbage this evening

and Sandy will send you an email or SMS when the time comes. There’s is much more possible using Sandy. I think you should take a look.

GTD and Vim outliner

Sun, 04 Nov 2007 21:14:24 +0100

I wrote an article about Getting Things Done using Vim outliner, an outliner for Vim.

The Perl survey results are in

Mon, 15 Oct 2007 14:42:48 +0200

The results for the perl survey are in. You can download the raw data from the results page. The analysis of the results will be on that same page in some time.

A visual explaination of SQL joins

Mon, 15 Oct 2007 13:10:13 +0200

The visual explaination of SQL joins contains the explaination of SQL joins that I never knew how to give. If you don’t understand joins completely, this will give you a visual model to help you understand SQL joins.

Sanitize your database inputs

Wed, 10 Oct 2007 14:10:37 +0200

I just saw this over on xkcd.

Picture of my new workbench

Tue, 25 Sep 2007 12:49:37 +0200

Here is a picture of my new workbench.

I created my own workbench

Thu, 20 Sep 2007 10:18:49 +0200

I created my own workbench a few days ago. I still have to put up a few photos, but maybe I will do that in a few days.

Creating the workbench was quite simple: I got an old top of a table and bought a piece of particle board for hanging tools. I also added eight power sockets so I can use my soldering iron, a power supply for 12 V and 5 V, a desk lamp and various chargers.

My new laptop

Wed, 05 Sep 2007 16:02:11 +0200

Yesterday I bought a new laptop. A Toshiba Sattelita Pro L40. When I tried to install linux it looked like it work pretty good. But when I tried to connect using the onboard wireless adapter I noticed an error in the dmesg output.

Today I thought of another way to get linux on my computer. I now use the preinstalled Windows Vista Business (reinstalled from the recovery disk) and vmplayer from VMware with a virtual appliance.

Create a sound generator with an NE555 IC

Tue, 04 Sep 2007 10:19:52 +0200

I few weeks ago I started doing some electronics projects. The second thing I tried was using the NE555 chip. It’s was quite simple to use. Within a few minutes I had a blinking led (remember, this is my third electronics project).

This video shows how you can create a sound generator with a few NE555 chips. I created something like it, a few days ago.

First results of perl survey

Tue, 04 Sep 2007 10:00:04 +0200

The first survey results are in about the conversion rates. There is still time to complete the questions. For all the reasons mentioned on the page: fill out the perl survey.

Scrape stuff of webpages

Tue, 04 Sep 2007 09:56:06 +0200

A web scraper in Perl, which uses a simple DSL for specifying what to parse. An example for the author follows. Web::Scraper hacks #1: Extract links linking to images

I'm unemployed (by choice)

Mon, 03 Sep 2007 17:11:49 +0200

For the first time in 1,5 years I’m unemployed. Not much of problem of course, because I chose to do it this way. I have all these projects waiting for me, but no time to work on any of them.

So I chose to stop working for an employer. Today is my first day without going to work. For a start I changed the the headers of this website and internettablet.nl. my Dutch website about internet tablets. I’m thinking about buying a server to host all my websites and a few others.

Vim page

Sun, 17 Jun 2007 13:42:26 +0200

Today I created a page about vim on this website. Vim is a useful editor, but sometimes it would be nice to have more articles describing the cool features that it has. The documentation describes every features in vim, but sometimes it’s hard to know where to start looking. I’m building this page with links to articles that describe features or general vim goodies. So enjoy!

SVN repository surgery

Sat, 05 May 2007 09:55:25 +0200

Once upon a time I had all my projects in one subversion repository. At first this looks simple, easy and useful. But after some time it will start to be a problem.

How can you fix your repository to have only one project in the repository. This is what I did, including sources that I used for help.

First I created a dump of the repository using the following command:

Archivemail

Sun, 22 Apr 2007 11:40:51 +0200

Once every few months I have to take a look in my received spam folder. I don’t like that, because it gets big and it takens a lot of time to load the headers. So almost every time when I look into this I remove all messages that are in there. It’s not that much work, but it takes some time, that I could spend doing something else.

A few years ago I used a program that would look through all the messages in a specified folder and then deleted all messages that were older than some number of days. The program is called archivemail and does exactly what I want. From today archivemail will delete all messages in my spam folder that are older than 30 days. I use the following command:

HOWTO Edit Messages

Sun, 22 Apr 2007 11:31:50 +0200

A few weeks ago I found this nice guide about howto edit and quote email messages.

Questions about Internet Tablets

Fri, 06 Apr 2007 20:46:42 +0200

ThoughtFix is asking questions about internet tablets. Here are my answers.

Do you own a Nokia 770 or Nokia N800? Yes, I own both.
If not, what keeps you from buying one today? N/A
If so: What do you use it for most? Music. Simple lookups of information. Watching videos.
What applications do you desire most? Canola-like email application.
What accessories do you desire most? Maybe, highspeed wireless internet everywhere?
If you could change the design, how would you do it? The camera is to much to the left (not really a problem, but could be better). The camera is useful, but only in bright light conditions. Overall I like the design.

A microblog

Sat, 24 Mar 2007 21:28:19 +0100

I started my first microblog. I created it using plagger and del.icio.us. To post an entry to the microblog, I have to post a bookmark to del.icio.us containing the tag microblog.

I currently use the following config file to create the page.

global:
  # Set timezone to your local one
  timezone: Europe/Amsterdam
  # this make logger logs important information
  log:
    level: debug

plugins:
  - module: Subscription::Config
    config:
      feed:
        - url: 'http://del.icio.us/rss/pstuifzand/microblog'

  - module: SmartFeed::All

  - module: Publish::Planet
    rule:
      expression: $args->{feed}->id eq 'smartfeed:all'
    config:
      dir: /home/www/microblog.peterstuifzand.nl/htdocs
      skin: microblog

I made a little change to the default skin. It showed an url to the feed from which the entry came, but I don’t need it, because I only have one feed from which all entries come.

Will HTTP Auth stop comment spam?

Sat, 17 Mar 2007 09:25:44 +0100

As an experiment I will try HTTP authentication to stop comment spam. The password is shown next to the chat button. I hope people will understand what to do. I also hope it will stop comment spam.

Big Brother State

Sun, 11 Mar 2007 20:13:31 +0100

A short animation about surveillance techniques used. The animation can be found at Big Brother State in multiple formats under a nice Creative Common license.

Power law tag size

Sat, 10 Mar 2007 12:30:33 +0100

Wij vervelen ons is my social concert calendar. It’s a calendar where people can put their favorite concerts. A few weeks ago I added a tag cloud. The tag cloud looked really nice because the tag with the most concerts was bigger than other tags. I hadn’t thought this thing out, so there was a hand coded 12-line if block that gave each tag a nice size and padding. This block didn’t use the max count of concerts so there was a possibility that that more tags got the huge size.

Craft your subject line

Sat, 24 Feb 2007 09:42:28 +0100

It looks like it still is to difficult to write a good subject line. Use words that mean something like names, places, dates or other nouns. It should be to the point and short. More information on The Effective E-mailer or my page about sending emails

I have a HTML feed available now

Sat, 17 Feb 2007 17:41:33 +0100

This afternoon I created a feed in HTML. It’s not useful yet, because the only useragent that will be able to read it is your webbrowser.

Of course curl and wget should work too, but they are not as useful for reading webnews. Less code, more content

Drawing 2

Thu, 15 Feb 2007 22:55:59 +0100

Drawing 1

Thu, 15 Feb 2007 22:29:21 +0100

At last: normal URLs for entries

Sat, 03 Feb 2007 21:52:48 +0100

At last my blogging software creates entries with normal, human-readable URLs. It was a simple change; it seems kinda strange that I haven’t changed it earlier.

We need an extensible remote control for N800 and 770

Wed, 31 Jan 2007 09:46:55 +0100

It looks like big buttons are in. Especially big buttons, that can be changed and be pressed.

The Nokia 770 (and N800 now too) needs an extensible remote control application, that will show buttons and start applications. It should be possible to start and stop music, choose a next song, call websites via wifi, open applications, connect my bluetooth connection. Just with a press of a button.

Is there anyone that knows an applications like this for the Nokia 770, or is there someone who knows how to write one.

Just one space

Thu, 25 Jan 2007 22:15:32 +0100

I always wondered why vim didn’t have the just-one-space function. It’s one of the most useful functions that is available during coding.

So today I tried to write one myself, the newsgroups and searchengines didn’t come up with something good. First of course it is a good idea to understand the effect of this operation. The just-one-space function removes all whitespace around the cursor and replaces it with one space character.

How to properly peel a banana

Mon, 08 Jan 2007 21:15:42 +0100

It looks like the internet is a giant lesson in synchronicity. Somehow it isn’t strange that the internet of all places is the place where all these synchronous things happen. There are so many people already in there.

Last week I was boring my colleague about how to peel a banana. And today I read an blog entry about it: How to properly peel a banana The author did a bit more research than I did and found this How to Eat a Banana: a Design lesson

Top perl Modules of 2006

Sat, 30 Dec 2006 16:32:15 +0100

I was thinking about writing a list of the perl modules that I used most often, liked best or somehow used. Some are golden oldies, others are new this year. There is no order in the list, so no Top 10 or anything.

DBIx::DWIW this is a module that helps writing database code. It contains methods for retrieving data and executing query’s. It removes almost all of the repetitive database coding work. It’s nice to be able to subclass and create a file with the configuration of the databases.

Using ruby to create vim extensions

Sat, 30 Dec 2006 16:16:53 +0100

Today a simple vim plugin is featured on the vim homepage: toggle_word.vim. I think the plugin in itself is not that useful, but it seems to be a good starting point for ruby programmers who want to create their own vim plugin and don’t know where to start.

I got a new keyboard

Fri, 29 Dec 2006 22:19:13 +0100

For the first time in years I have my own split layout keyboard. I works really great; it’s the same as the one that I use my job. My typing speed is actually increasing with this.

Slowchat

Tue, 05 Dec 2006 23:12:17 +0100

Hmm slowchat. Why would anyone want it? I created this little piece of slowchat goodness on the right side here.

Post some nice messages. The winter is coming and it could be cold. Show me some love :).

RSS feeds are not a problem anymore

Wed, 15 Nov 2006 22:14:00 +0100

For the last few months I was using Plagger to read RSS feeds. These feeds would be downloaded and send as e-mail to my gmail account. There was not a lot wrong with this. But as always there was a better way.

A few days ago I changed Plagger to check twice a day. Once around 9:00 when I arrive at work and once at around 19:00, which is when I’m back home and sitting behind my computer.

Subversion diff inside Vim

Mon, 06 Nov 2006 21:49:55 +0100

I like using vim. It is simple want it to, but has a lot of possibities when you need them. Like Perl in vim simple things are easy and hard things are possible. Like the following piece of code.

I wanted to see a diff of my current version and the version in my svn repository.

function Svndiff()
    let file = system('tempfile')
    execute 'silent !svn cat ' expand("%") ' > ' file
    execute 'silent vertical diffsplit ' file
endfunction

map <F4> :call Svndiff()<CR>

Of course the <F4> binding is like icing on the already delicious cake. The only thing that I’m not happy about is the problem with the tempfile, that will stay open after you’ve opened the split screen.

External programs in Vim

Wed, 01 Nov 2006 22:12:45 +0100

When you’re typing some text in Vim, you will sometimes need a piece of text that is easy to generate on the command line or with a simple perl script. Maybe you want to insert the current date, a simple calendar or a list of day names.

Don’t you worry there’s a simple vim command that will help you with this. Here are some examples. From simple to complex.

Insert the current date

Nokia 770 is back

Thu, 19 Oct 2006 20:00:16 +0200

A few days ago I received a Nokia 770 back. It’s not the same as I sent. The one that I send had a gray/white screen. Which wasn’t very nice. The new one has a working screen and the 2006 version of the firmware. It works great. Especially the new thumb keyboard.

My very own ticket system

Wed, 18 Oct 2006 21:38:57 +0200

I created my first Ticket System. It may look a bit like RT, but that doesn’t matter to me. The code was written from scratch in about 12 hours.

I used DBIx::DWIW, HTML::Template, CGI::Session and Web::Controller. This last module was created by myself, to make it easier to create web applications. The other modules weren’t written by me, but did make it easier to create this application.

I created a demo version of the ticket system. You can login using: demo/demo. So give it a try and send me your opinions.

Birthday 23

Tue, 03 Oct 2006 07:35:27 +0200

It’s my birthday again. I’m 23 now. I bought some pies for the people at my working place; ‘Herfstvlaai’ and ‘Appelkruimeltaart’. So there are a lot of apples in there. It’s early, but I already have my first present. It’s a book called the Tipping Point. I haven’t read it yet, so I can’t tell exactly what it’s about. You should read the website for that.

I hope the rest of the books will arrive today, but you can’t be to sure about things like that; so probably it will arrive this week.

Impossible? Now is it?

Sun, 27 Aug 2006 20:57:32 +0200

“The person who says it cannot be done should not interrupt the person doing it.”

– Chinese proverb

Lowlands was fun

Tue, 22 Aug 2006 21:23:47 +0200

It’s a shame that Lowlands only lasts for five days. That is about the most one can get out of it. I saw some bands but not as many as I would have liked, because of a stupid programming error (not like the ones I usually make). Of the four bands that I wanted to see, three where programmed on the same day at about the same time: Pennywise, Nomades et Skaetera and Danko Jones. But that doesn’t matter; I saw Pennywise and Danko Jones and they both played a great show (Pennywise was better, actually).

Making modification to dwm is really easy

Wed, 16 Aug 2006 21:27:19 +0200

Dwm is the ‘dynamic window manager’ and is written in only 2000 lines of C code. This is quite nice. The size and the quality of the code is really good, so its really easy for me to make some modifications.

The first modifications that I made, where for keys to start programs. F2 now starts the terminal and F4 starts a webbrowser. F3 starts gmrun, but I’m not sure if I need, or that I like it. Some people use it, some people like it, but most of the time I just use a terminal. Its already open, so. The thing is: in Ion3, F3 opens a query window just like gmrum and lets me start a program.

Lowlands is only one day away

Wed, 16 Aug 2006 15:44:30 +0200

Tommorrow around this time I will be almost one my way to go to Lowlands. Lowlands is a festival with all kinds of different music. The big names for me this year are Danko Jones, Pennywise and Less than Jake. Of course there are many bands that I’m going to see, but which I not yet know.

Last year I didn’t go, because it somehow had a different thing I had to spend time on. So let’s see what’s going to happend this year.

Another window manager

Wed, 16 Aug 2006 15:36:31 +0200

It seems I’m always on the lookout for new windowmanagers. Last year started using Ion3, which I really like. Yesterday I saw a windowmanager called dwm and it is written in about 2000 lines of C code. This is not useful in itself, but it makes it easier to understand the code and make some small modifications without actually understanding all of it. And 2000 lines isn’t that much either.

Configuration of dwm is done through editing the source code of the program. Which is actually quite a simple way to make changes.

Traveling is fun

Mon, 14 Aug 2006 22:47:04 +0200

Sunday I returned from my nine day long trip through Europe. This is one big lie, because Europe is bigger than just Brussels, Paris and some parts of the Netherlands.

Still, such a trip can be a fun thing to do. I had a few to do it, so its not that big of a problem. Still I like to make a bigger trip next year. Still trough Europe, but a few more weeks and a few more countries.

Deploying web applications

Wed, 26 Jul 2006 21:43:41 +0200

Deploying stuff is hard enough already. And so it shouldn’t be made harder by code that isn’t in source code repositories. Read my latest article about these kinda things and some ways to make that whole thing a bit better.

The two things that I forgot to say are:

make it repeatable,
make in one command.

Plagger: a platform for feeds

Sun, 16 Jul 2006 22:24:13 +0200

While I was reading the Perl planet I found a link to a project called Plagger. It’s system for creating, changing and publishing feeds.

To create a new ‘program’, you need to make a config file. The example directory includes a bloglines2gmail config and a config for a ‘planet’ aggregator. Both are less than twenty lines of configuration. It’s really easy to create your own feeds with this.

Be sure to check out the presentations on the website, for an explaination of Plagger (the documentation is a bit light).

Some nice things about the Nokia 770

Sat, 01 Jul 2006 12:09:53 +0200

The Nokia 770 has Bluetooth, which allowed (see previous post) me to connect to the internet. The connection to internet can be created in two ways, one was by using my phone (A Nokia 6021), which worked without any problem (except for the money bit), or by using a bluetooth attached to a linux PC with some iptables magic.

Both ways work like a charm, but the second one is a bit difficult to configure. It would be nice if the Bluetooth via the PC would as simple as Bluetooth via a phone.

Nokia is broken

Sat, 01 Jul 2006 11:39:24 +0200

Even before I had the time to write about the arrival of the Nokia 770, with some nice pictures, it is already broken. It seems like it’s a common problem with newer devices.

The problem is that the screen is white with gray lines. I couldn’t find a picture of it on the web, so I will post a picture of my own device. See:

So this means that I’m not that happy, at the moment. Still, this device is going back to Nokia and I hope they will be able to fix it, because this device is so nice, and it works great.

A Nokia 770

Wed, 28 Jun 2006 21:15:55 +0200

I bought a Nokia 770. Hopefully it will arrive tomorrow. I don’t what to write, yet. But I will some more to say, when I have my own 770 in my hands.

At the moment perhaps, you should take a look at kla.as for Nokia770 screenshots.

A clipboard webservice

Mon, 05 Jun 2006 15:43:53 +0200

This is my first test with my new webbased clipboard system, everybody can copy a piece text to the server. When you want to paste the text again, you can do that from any computer that has an internet connection. The last thing you need is the code that you got when you copied the text.

One thing left to say: don’t send in stuff that you don’t want anyone else to read. The text is saved for about one hour (actually between one and one-and-a-half hour). Alsa anyone with enough time on his hands could go and guess the codes; so don’t do it, or don’t care; both will work. I’m not responsible and warned you.

My new photo gallery

Sun, 04 Jun 2006 21:02:10 +0200

Just two weeks ago I bought a new digital camera. It’s a Panasonic DMC-TZ1, which I’m pretty happy with. The nice thing about this camera is, that I can take pictures with it.

The pictures I took are visible on my new photo gallery. So take a look. Obvious about the pictures is that I still have a lot to learn about taking pictures in dark places.

A new website about stuff

Sun, 07 May 2006 17:43:58 +0200

A week ago I created a website about stuff. The layout is and will stay as simple as it is at this moment. At the moment it’s mostly programming related articles. But one could expect more and different texts.

Een fijne zondagmiddag

Thu, 20 Apr 2006 22:40:56 +0200

This sunday there are a few bands coming to Sneek. It shall be a pretty nice sunday afternoon. At least much better than the that you could normally do.

Bands: Roger Miret and the Disasters, Demented Are Go, The Bones, Heartbreak Engines o.a. Some people will call it a good warming-up for Groezrock.

This stuff is pretty brilliant

Thu, 20 Apr 2006 22:35:41 +0200

This one is about birds. Look around the archive for more of this kind of comics. Especially the comics and drawings about the monkey named Mojo, are worth a good look. Check it out!

Groezrock 2006 is not that far anymore

Tue, 18 Apr 2006 21:36:03 +0200

There are only two weeks left till Groezrock 2006 starts. And the program is pretty amazing:

MAINSTAGE  Friday, 28th of April 2006 - Doors : 17:30 u. ...:

    17.45 u. 18.10 u. : Say Anything
    18.30 u. 19.00 u. : Aiden
    19.20 u. 19.55 u. : Silverstein
    20.15 u. 20.55 u. : UnderOath
    21.15 u. 22.00 u. : Goldfinger
    22.20 u. 23.10 u. : Thrice
    23.30 u. 00.30 u. : Taking Back Sunday

SECOND STAGE  Saturday, 29th of April 2006 - Doors : 10:00 u. ...:

    11.00 u. 11.30 u. : The Banner
    11.55 u. 12.25 u. : The Spirit That Guides Us
    12.50 u. 13.25 u. : Officer Jones & HPCP
    13.50 u. 14.30 u. : The Maple Room
    15.00 u. 15.40 u. : Bold
    16.10 u. 16.50 u. : Himsa
    17.20 u. 18.05 u. : Raised Fist
    18.35 u. 19.20 u. : Comeback Kid
    20.00 u. 20.45 u. : Born From Pain
    21.30 u. 22.20 u. : All Out War
    23.00 u. 23.50 u. : Path Of Resistance

MAINSTAGE  Saturday, 29th of April 2006 - Doors : 10:00 u. ...:

    10.30 u. 11.00 u. : Latterman
    11.20 u. 11.55 u. : A Wilhelm Scream
    12.15 u. 12.50 u. : Peter Pan Speedsrock
    13.10 u. 13.50 u. : The Lawrence Arms
    14.15 u. 15.00 u. : Death By Stereo
    15.25 u. 16.10 u. : Anti-Flag
    16.35 u. 17.20 u. : No Use For A Name
    17.45 u. 18.35 u. : Less Than Jake
    19.00 u. 20.00 u. : Sick Of It All
    *20.30 u. 21.30 u. : Me First & The Gimme Gimmes*
    *22.00 u. 23.00 u. : Dropkick Murphys*
    23.30 u. 00.30 u. : Bad Religion

More info can of course be found on http://www.groezrock.be. So take a look. And go.

EU registration stuff

Sat, 08 Apr 2006 10:14:27 +0200

Yesterday was a crazy day. It was the third phase of the .EU domain registrations and everybody could try and get a domain. Not everyone got what they wanted but I am still very happy with the two domains I got: stuifzand.eu and hobby-koopjes.eu. The last one is of course a little present for my father and will become the european version of the webshop hobby-koopjes.nl.

After this day, normal registrations will start, but almost all good domainnames are already gone (about 400_000).

Even my homebrewn comments are not comments spam free

Fri, 24 Mar 2006 22:44:18 +0100

While I was working on the code that works with my comments, some bot posted a spam comment. I thought that would only work on weblogs that use popular software. Maybe my site uses names that are obvious enough for a bot to find out.

As it’s not possible to post html or other markup to my comments, the entry is show as text and isn’t harmful (or useful) to anyone.

Synchronization for my phone

Sat, 18 Mar 2006 22:57:17 +0100

Now that I have this nice phone, I’m looking for a way to synchronize my contacts, calendar items and todo lists. On Windows there is the Nokia PC suite, but that won’t work on linux.

I already found gnokii and Multisync, but the first is not usable enough and I can’t get the second working with my phone. The first problem could probably be solved by using some scripts, but I was looking for an easier solution, like a one click synchronize.

Aliennation is nominated for best band of March

Sat, 18 Mar 2006 22:30:19 +0100

Aliennation is nominated for March Metal Madness and needs your vote to get to the next round. So wait no longer and go take a look and listen to the songs on the website and cast your vote.

I have a job

Wed, 15 Mar 2006 21:52:27 +0100

Ok, so I already have a job for about three weeks, but still. It’s great. All day long Perl programming. What more can one ask for?

I’m not sure I can tell about the company I work for, so I won’t.

My new telephone

Sat, 11 Mar 2006 21:18:28 +0100

For the first time in two years I have a phone. It’s a Nokia 6021. I would like to try and write some software for it. Maybe it’s possible, or maybe not.

The phone has Bluetooth support and is actually quite simple. So that’s good. I hope it will work with linux. You never know.

When you read this and you think you need my number, please send me an e-mail.

Added comments to the weblog

Sun, 19 Feb 2006 17:15:17 +0100

Ok, I think it’s time for this. I added the comments feature to my website software. It works really great now.

It was a problem when I couldn’t add comments, because the pages are static. It can be made, so I did.

Graduated

Sat, 04 Feb 2006 13:50:35 +0100

Yesterday was my final presentation about the Home Automation project. I graduated. So that’s nice. Now I have to find some kind of income.

A new website: Imba-nator

Thu, 02 Feb 2006 10:53:31 +0100

Yesterday I created a new website. Everyone can type statements. After that people can vote about the Imba-ness of the statement.

Check it out: imba.peterstuifzand.nl.

Firefox crash in debian

Thu, 26 Jan 2006 22:49:58 +0100

I experienced some problems while using Firefox on Debian. With the use of google it was fixed.

Firefox segmentation fault debian work around. This bug report contains a work around.

Hit-a-Hint extension for Firefox 1.5

Wed, 18 Jan 2006 14:58:12 +0100

I just noticed that the Hit-a-Hint extension is upgraded for Firefox 1.5. This is great because it will let click links and buttons without using the mouse.

When I installed it there was one problem though, it didn’t work. The solution was found quickly. Goto about:config and search the key extensions.hah.hints.tags and change that to:

//a|//input|//textarea|//select|//button|//isindex|//frame|//iframe

and it will work. I’m not sure what the problem was, but this will at least make it work.

Alt stopped working in rxvt-unicode

Thu, 12 Jan 2006 13:37:05 +0100

My Alt key stopped working in rxvt-unicode. Still works in Firefox. I don’t have any idea about how it stopped working. After some searching and trying, I found out that I had to add a line to my .Xdefaults file.

URxvt.modifier: meta

After reloading the file with xrdb -merge ~/.Xdefaults, the Alt key started working again as it did before.

Added hoodwink.d to my website

Tue, 10 Jan 2006 22:57:44 +0100

I added hoodwink.d to my website. It’s an comment system on top of websites. This is really nice, because my website is based on static webpages, which makes it hard to add comments.

Go to the hoodwink.d to install it and post some ‘winks’ here.

Problem with feeds

Wed, 04 Jan 2006 20:28:13 +0100

One of the problems with feeds (RSS, Atom, or something) is that most of the explaination is about XML and the technology behind it and not about the problem it solves.

I would be better if explanations about feeds wouldn’t talk about XML or other technology parts, when explaining it to users.

Weblogs looking like spam websites

Fri, 30 Dec 2005 16:43:35 +0100

Sometimes there’s a website that you visit which has the same properties as a spam weblog. The website just looks like a spam weblog. Most of these websites are based on free templates or free weblog services. I’m talking about weblogs of Blogger with the standard templates, but any service and template will do. This is the one I used.

The spam is a problem on its own, but I have another problem with it. Sometimes real websites look like spam weblogs. I had two weblogs on which I wrote, but after some time I couldn’t anymore. Just because it felt wrong. I moved all my weblog writing efforts to this website and I created my own design.

Faster ADSL by changing the cable

Wed, 28 Dec 2005 00:19:31 +0100

At the end of this year the download speed of our ADSL subscription is increased to 6 MBit/s. The problem was that somehow we did get less than 1 MBit/s. This problem was fixed by making a new cable to the ADSL router/modem. The new problem now is that I don’t have a clue about why this cable is better than the previous one.

Interesting upcoming concerts

Tue, 27 Dec 2005 23:44:45 +0100

As always while adding concerts to my concert website, I saw a nice concert. This time it’s a concert of The Slackers. Another one is the Paaspop Festival. I’m not sure if I will be going to one of these, but it’s very tempting.

Perl Testing Book Received

Wed, 21 Dec 2005 20:39:09 +0100

Yesterday I received the Perl Testing Developers Notebook. It only took about six days to get here, but it still is three months ago, since I won. Of course this is no problem and I’m very happy with the new book.

I like to thank Josh, for the contest. Which was actually quite easy :).

I’ve started reading it and it looks like it contains real nice examples for perl testing. Some stuff that will be really useful, when I’m working on the webshop and the concert website.

Subject of my weblog

Mon, 19 Dec 2005 21:49:34 +0100

I’m not yet sure what this is, but it looks like some kind of end of the year post. But were still two weeks of.

Somehow a lot of my posts are about programming and computers. This is kind of stupid, because I do a lot of other stuff besides programming. While it may look like it, I’m a big fan of all kinds of punk, ska, rock’n roll and reggae music. This would become obvious if I went to more of those concerts, but their are hard to come by in this neighbourhood.

Music Player Daemon

Sat, 10 Dec 2005 15:25:46 +0100

I thought about how a daemon program could be easy to use for playing music. So I started with some research by googling for ‘music player daemon’. And the first result was a link to a program called ‘Music Player Daemon’.

This program runs in the background and can be controlled with php based websites or a command line tool. This is nice separation of concerns. So I installed the package and tried it. I’m really impressed by how it works, especially with the client tools, that let me select the music. The thing that I don’t like is that I have to create playlists. But with one playlist containing all the songs is easy to create.

Revenge of the Rock'n Roll Monsters Tour

Sat, 10 Dec 2005 14:49:26 +0100

Revenge of the Rock ’n Roll Monsters, what a show. This was best thing since some other concert. All the bands played really well, and it looked like they we’re having fun. Which make the whole thing just better. It was very much worth the trip to Zwolle and the € 15,00.

Tonight we’re going to Music For All Ears, which is organized by the saidia foundation. This organization helps motivated and talented students from developing countries to study in Groningen.

A ftp deployment tool: ftpup

Sat, 26 Nov 2005 17:05:24 +0100

This weekend I wrote a ftp deployment tool. It helps me deploy my changes faster to my concert website.

The program is written in ruby. It will search for the file .ftpup in this or a higher directory. In this file you can specify some rules that let the program know where to upload the files to.

The rules use regex to specify where the file should go. To let this approach work as it should, it will first find out where the file is, relative to the project ‘basedir’. The basedir is the directory where the .ftpup file is.

Using ruby-xosd to show a timer

Thu, 24 Nov 2005 23:13:49 +0100

After the articles on 43folders about using timers for specific things, I thought I would create a timer program. Now I have a few programs that I ‘integrated’ in my window manager. With Alt-F4 ion3 will show a query. I can type the number of seconds the timer should run for. A timer is shown in the lower right corner of the screen (which is already evil enough).

A next version will probably make it possible to show and hide with a push of the button.

My new repository uses Darcs

Thu, 24 Nov 2005 22:50:51 +0100

Darcs is a distributed revision control system. It can be used to keep revision of documents (which includes sourcecode). I tried to use it to keep some projects. The repository is online at http://darcs.peterstuifzand.nl and is read-only.

The nice thing about darcs is that anyone can be get a version of the repository on his own computer. That repository is a complete repository and can be used to keep revisions locally. Changes can be push-ed to or pull-ed from the remote repository. This makes it easy to work on a local copy, while keeping different revisions (actually patches).

Externals editors in Mediawiki

Tue, 15 Nov 2005 20:41:21 +0100

The new mediawiki supports external editors, this is about the same as the hack I posted a few days ago. The nice thing about it is, is that you can edit about any file or page that’s uploaded or written.

The page edit part of the program very much like the program I created. The only problem is that it uses regexe instead of a more stable solution like WWW::Mechanize. The support for editing files is really good.

Programs I currently use

Sun, 06 Nov 2005 18:11:45 +0100

A short list of the applications/programs that I use.

vim - an editor
rxvt-unicode - a xterminal
ion3 - a window manager
firefox - a web browser
mutt - a mail client
raggle - a rss reader
playmusic - a music player
vim outliner - a todo list/outliner tool
irssi - an irc client
bitlbee - a irc server/instant message gateway

Time in a packet

Sun, 30 Oct 2005 04:01:13 +0100

I was so nice to create a package for osdtime.

Source

osdtime-0.1.tar.gz.

On screen time display

Sun, 30 Oct 2005 03:50:18 +0100

Today I liked to know the time. I don’t have a clock and on my computer it’s to much work to show the time. I use ion3 and it can show the time in a statusbar, but I don’t like that, because it takes too much of my screen real estate.

So I created a little program that shows the time for a few seconds in the right bottom corner of my screen. It’s called (how original) osdtime.

Using a script to update Mediawiki

Fri, 28 Oct 2005 22:41:59 +0200

I created a script that allows me to update a page on a media wiki. It uses WWW::Mechanize, IO::All and Config::Std. The last two modules aren’t needed probably. But it makes it all a lot simpler.

#!/usr/bin/perl -w

use IO::All;
use WWW::Mechanize;
use Config::Std;

read_config "$ENV{HOME}/.mediawiki" => my %config;

my $username = $config{login}{username};
my $password = $config{login}{password};
my $hostname = $config{login}{hostname};

my $title = $ARGV[0] or die "usage:   mediawiki [page title with under scores]\n\n";
my $url = "http://$hostname/mediawiki/index.php?title=$title&action=edit";

my $ua = WWW::Mechanize->new;

my $login_url = "http://$hostname/mediawiki/index.php?title=Special:Userlogin&returnto=Main_Page";
$ua->get($login_url);

$ua->field('wpName', $username);
$ua->field('wpPassword', $password);
$ua->click('wpLoginattempt');

$ua->get($url);

$ua->form_number(1);

my $form = $ua->current_form();

my $tmpfile = io('/tmp/mediawiki-1');
$form->value('wpTextbox1') > $tmpfile;

system('vi /tmp/mediawiki-1');

$tmpfile->open('r');

my $content = $tmpfile->slurp;
$ua->field('wpTextbox1', $content);
$ua->click('wpSave');

print "Done!\n\n";

The configuration is read from /home/$USER/.mediawiki. It should look something like this.

Plugins with perl

Sun, 23 Oct 2005 21:26:31 +0200

This post is not about perl plugins (what would that be?). But about programs that use plugins. One of those programs is Qpsmtpd, a perl mail server. They use a special and very nice way to use plugins.

Moveable Type is another perl program, that uses plugins. These plugins are a little bit simpler than the qpsmtpd plugins, but just as powerful.

And now there is another perl program that uses plugins, my webshop. It is really nice to see how easy it is to create a new type of shop on top of the current code. I can’t yet show it, but within a few days it will be online.

Another music player

Tue, 18 Oct 2005 14:40:33 +0200

The day after I posted the previous post, I became aware of a serious flaw in the design of the player. It couldn’t play music from on artist or one album. I really liked this functionality, so I wrote it.

MUSICDIR=~/music
cd $MUSICDIR
find . -type f -name "*.mp3" -o -name "*.ogg" | grep "$1" > playlist
mplayer -quiet -shuffle -playlist playlist | grep Playing

Also it tried to play the cover images that are in some of the directories. This was solved by specifying the extensions of the files to play.

My new music player tool

Sun, 02 Oct 2005 22:14:30 +0200

Today I created a new music tool quiet like the Apple Shuffle. It will play music files randomly from my ‘collection’. Here follows the code.

#!/bin/sh
cd ~/music
find . -type f > playlist
mplayer -quiet -shuffle -playlist playlist | grep Playing

It can be started in it’s own terminal and be controlled with all the normal mplayer combinations. PgUp and PgDn will skip songs. Left and Right will skip in a song. + and - will change the volume. Q let’s you quit.

A code generator

Sat, 01 Oct 2005 17:56:48 +0200

At the company, where I’m doing my internship, I needed a code generator for some C code. There was some C code needed. So I started of writing it. After some lines, there started to show some patterns, which could be easily handled by some description language.

The first description language was a line based format. First a line with the name of the object. And after that the names of the functions. This format is easy to parse and easy to use. The output was done with print statements.

I won the new Perl Testing Developer Notebook

Wed, 07 Sep 2005 20:32:17 +0200

I won the Perl Testing Developer Notebook written by Ian Langworth and chromatic on perlcast.com. I’m curious about when the book will arrive.

Weblog now contains monthly archive pages

Sat, 03 Sep 2005 17:52:18 +0200

Today I added monthly archive pages on this weblog. The design is not clean yet, but it works, like you can see at the archives. The archive page now contains a list of links to the pages of the months with posts.

The archive first contained a pages with all the posts, which uses a little little too much bandwidth. This new approach uses just a little.

AlienNatioN has a new website

Sat, 03 Sep 2005 15:44:47 +0200

On Martijn’s weblog I read that AlienNatioN have a new website. He’s their bassplayer. It looks pretty, but it’s full of Flash. And as of you may know, I don’t like Flash. The good thing is, is that the website is not totally Flash.

Most of the parts are visible even if don’t have a Flash plugin (some people don’t have it), and that’s good. But you can’t get past the intro, because there is no link.

Hoodwink.d and MouseHole

Sat, 03 Sep 2005 12:46:02 +0200

MouseHole is a proxy that has the ability to rewrite webpages, just like GreaseMonkey, but instead of using JavaScript it uses Ruby.

Hoodwink.d is a comment system that is added by MouseHole to weblogs. It’s a really nice way to combine serverside, with clientside.

This combination create the possibility for people to add comments to all kinds of websites.

What other things could be done to by using technology like this?

What have I been up to the last three months

Wed, 31 Aug 2005 14:26:36 +0200

Here I’m back again. Maybe you missed me, maybe not. The problem is that my computer’s harddisk crashed. That’s a whole lot of crap. And until recently I didn’t have time to get this website working and updated again.

During this three months most of my time was invested into my first actual website project with a domain name and all. I created a web application in Perl, that is running that website.

Garbage Collection in Ruby

Mon, 27 Jun 2005 15:56:44 +0200

why published a nice article about garbage collection in ruby. It shows some problems and how these can be solved by changing some of your ruby code.

Create notes from webpages with Scrapbook

Mon, 27 Jun 2005 00:41:32 +0200

With Scrapbook you can create notes from webpages, or save complete websites on a specific date. So this extension is helpful when you're a writer, or a researcher.

Problems with tools like these is that you have to find some place in your workflow to use them. If you don't have a place it is possible that I will stay in tools menu for a long time without you using it.

This Delicous Tool is pretty cool

Sun, 26 Jun 2005 14:44:42 +0200

At lifehacker I came across this incredible tool for del.icio.us. It is called the del.icio.us Direc.tor. It a combination of webapp and del.icio.us API and Ajax.

This probably is one of the steps were going to see on the web, web applications that are written over webbased apis. Web based tools with nice user friendly clean interfaces that do something that's different enough from the actual data provider website.

Very impressive. We need more of this.

Migrated CVS repos to subversion

Sat, 25 Jun 2005 14:50:14 +0200

Today I have migrated a CVS repository to subversion. It was quite easy with a cvs to subversion migration howto.

The stuff I transmitted was this website. About three months ago I started using subversion. At first it was a try only, but now I use it for three projects and a website. I really like it. The nicest commands are the revert and status command. This is stuff that programmers really need to know and use, even if you're one programmer working a project.

Two new articles

Fri, 24 Jun 2005 18:03:17 +0200

I have written two new articles. First is about using time based movement in a computergame. The other is about creating a Java/Swing GUI with RiverLayout. I will also try to create more articles about GUI programming in java and maybe about using invariants and contracts in object oriented programming.

My first game programming article

Sat, 18 Jun 2005 14:43:40 +0200

Yesterday I have written my first article about game programming. I have ideas for some other articles that I will write in some days. It's really fun to write, but I'm not yet sure if there are people who think the article is helpful.

I would appreciate comments, ideas, suggestions, feedback about the article.

Webwinkel Reloaded

Mon, 06 Jun 2005 16:53:19 +0200

Hobby-Koopjes.nl has been upgraded multiple times. I've added all kinds of functionality.

New products
Links to other pages
Ability to specify if a product should be put into a packet.
Some cleanups of the order database code.

All in all not that many upgrades, nut at least the structure of the code is better suited now to be used with the order/billing code.

Robochallenge Recap

Mon, 06 Jun 2005 16:47:11 +0200

Some time age I posted an entry (actually the previous one) in which I explained about the project I would be working on for some time. The project is about to end. We only have to deliver some documents (system documentation) and then we're done.

I'm not yet sure what to tell, but at least I can tell that we've failed. We didn't win any prices. Maybe that's not the point of the project.

RoboChallenge

Sat, 11 Dec 2004 21:34:00 +0100

This is the first post about my internship. Actually it’s not really an internship, but it’ll do for the explanation. The idea is that we make a robot. It’s not as futuristic as it sounds. The robot will compete in a challenge.

In this game the robot has collect as many balls as possible. These balls have different colors and sizes. Our robot uses digital camera’s to find the balls by taking pictures.

The new hobby-koopjes website is online

Sat, 13 Nov 2004 17:19:53 +0100

It was hard work, but at last a new version of the hobby-koopjes.nl website is online. It has become a nice website, with an interface that’s actually quite pretty.

CD Ripping on Debian

Sat, 23 Oct 2004 01:31:04 +0200

Today I fixed my computer. It now will rip cd’s, without being really slow. Actually I only had to install a new kernel. I now use 2.6.8 instead of 2.6.7.

Ripping cd’s with sound-juicer is really simple.

A Webmail To RSS tool

Mon, 18 Oct 2004 16:33:00 +0200

At my school we now have to use a webmail client. And I don’t like it. Because it is a lot of work to open up the page, enter a password, look over the messages and find nothing new.

I use Liferea as my RSS Feed Reader and it now uses a program to get a feed of the messages. The program downloads the webpage with the messages and then generates a simple rss2.0 feed from that.

To the Toydolls

Wed, 13 Oct 2004 23:49:10 +0200

We are going to the Toydolls. They will play at the Oosterpoort in Groningen on 21 november. This is going to be so much fun. And the tickets are only EUR 15,- + EUR 3,30 administration costs. TicketService is the best there is :)

Birthday

Sun, 03 Oct 2004 20:20:51 +0200

I am 21 now. Ole.

Notemanager Webapp

Sat, 02 Oct 2004 00:52:04 +0200

Today I started with the creation of a webapp, in which you can make notes. It’s really simple, but already it has some nice features, like categories. It is written in ruby and uses YAML to save the notes. This makes it easier to save and load the notes.

Tray Icon applet to add pages to blog

Fri, 01 Oct 2004 00:10:53 +0200

Inspired by Tomboy and GnomeTrashApplet I created a TrayIconApplet to add pages to my weblog. But it’s not written in C or C#, but in ruby using it’s Gtk wrappers. And it was easier than I at first thought.

It’s a application around pages. And has the following features.

listing web pages on website
editing web pages on website
listing all weblog items
adding new items to weblog
generating the website

It’s a really nice app. But it’s still has lots of bugs, probably. And some stuff is not yet good enough, like the interface of the editor. It could use some extra buttons and menus, a better font (monospace at least). Also it doesn’t update the lists of pages in the interface.

Nightly Build

Wed, 29 Sep 2004 02:26:28 +0200

I’m thinking of creating a nightly build of the webshop I’m working on. But what is a nightly build or what should it do?

get newest files from CVS
prepare/compile files
install files to some directory that’s visible through the webserver
run all tests
create all kinds of reports

Possibly it should do more, but this is at least some of it.

Bugfixing and rss feed

Tue, 28 Sep 2004 11:24:03 +0200

After some bugfixing, I now have the permalinks working right. I also added an RSS2.0 feed. I’m not yet sure if it’s the way I like it, or that’s correct. But it’s a test so.

Lars Frederiksen And The Bastards

Mon, 27 Sep 2004 19:46:09 +0200

Saturday evening I went to Lars Frederiksen And The Bastards with some friends. It was in the Melkweg in Amsterdam. That night there played three bands.

The Heartaches
The Selecter
Lars Frederiksen And The Bastards.

I was really fun to these bands live. Especially since I didn’t know, the Selecter also came to play some songs. I haven’t seen any of these bands before, but they were all really great.

Website generation software

Mon, 27 Sep 2004 17:48:19 +0200

The website generation software I use has a few little flaws.

It uses the filename for the date. (e.g. 20040927174819.tp)

This actually goes two ways. On the one hand it’s a unique name for the file. On the other hand, it has metadata on the outside of the file.
There’s no easy way to add more data to an entry. (e.g. I can’t add category’s)

Actually I can but then I’ve to change the entry format.

My New Debian Setup

Mon, 27 Sep 2004 17:45:03 +0200

Yesterday I installed a new Debian setup. I used Redhat before, but I began to show signs of old age.

Now I have Gnome 2.6 and some more nice stuff. There are some many packages, that I’m not yet sure what to install.

GMail account

Wed, 22 Sep 2004 10:26:22 +0200

I got my first GMail account. First I’m just going to look at how it works. If it’s as nice as the other people on the web told.

It’s all really crazy around these accounts. I just found a website that helps people to get a GMail account. GMail Swap, and in other places people are trying to sell them.

There are also people concerned about privacy issues.

New Weblog Software

Tue, 21 Sep 2004 21:16:44 +0200

I created some new weblog software for myself. It’s written in ruby, uses BlueCloth, and is very simple.

Actually it’s a part of a system that’s a little bigger. That system generates my webpages. To create a website you only have to write the content, all the stuff is automatically created.

Gaim 1.0.0 has appeared.

Sat, 18 Sep 2004 13:40:17 +0200

Gaim 1.0.0 is ready! It’s very nice. It has really improved in the last year. All the features like fileupload/download and the little picture of other people (and yourself) are implemented. Furthermore it can connect to multiple protocols at the same time.

Return from the roadtrip

Mon, 09 Aug 2004 11:25:50 +0200

Saturday I returned from my roadtrip. Now is a good time to tell what we have done.

Sunday

First we drove to Geneva, Switzerland. We took the autobahn through Germany. We stopped a few times. When we we’re in Switzerland out first stop was in Basel, where we took a look at a local Mac. We didn’t we would be staying that long, when we saw the prices there.

We arrived in Geneva at about one in the afternoon after a drive of about 13 hours. We spend there two nights on a camping. Real nice, and not even that expensive, about 10-15 Swiss Franc a night. That’s less than EUR 10.

Weblog gui tweaks

Fri, 23 Jul 2004 16:31:08 +0200

Today I also made some tweaks to the layout of my weblog. It’s really nice like this. Some extra space between post of another day and earlier posts.

Radio Interview

Fri, 23 Jul 2004 16:20:28 +0200

The radio interview is done. I’ve put on the website of the roadtrip. It’s dutch, so I think not everybody will be able to listen.

SpringLayout is really nice

Thu, 15 Jul 2004 00:48:05 +0200

Today I was creating some panels for webshop manager program I’m creating. I used SpringLayout for this. It’s really nice, also because I found a class called SpringUtils on java.sun.com somewhere in a tutorial. With this class you can connect the components on a page. And they will be shown in a table-like fashion. At last it’s possible, for me, to create nice and professionally looking interfaces using java.

But the strange thing is that when I tried to create the same interface using gtk, I was done in a about five minutes.

GridBagLayout is evil!!

Wed, 14 Jul 2004 17:24:24 +0200

Yesterday I found an animation on the web. It will show you why gridbags are evil. It’s briljant. Especially because I coding a GUI myself, yesterday. An I was about to use the gridbag and the memory came back to me…

Totally Gridbag

Forum improvements

Wed, 14 Jul 2004 14:16:01 +0200

It’s still needed to create a better forum. I’ve have installed a forum on the roadtrip website, but their is nobody that posts a message.

I would be nice if someone would post a message, but if you need to register to read the forum, a lot of people will not try it. Some people have done research on this. And I think it’s true. There was also a problem with some cookie stuff, so people couldn’t login.

The roadtrip

Wed, 14 Jul 2004 02:29:59 +0200

In about 10 days, four of my friends and I, are going on a roadtrip. We’ve bought an 10 year old van. With this van we’re going to make a trip to Geneve, Italy and Croatia and back. We’re are probably going to make some movies to show, when we’re back.

I think I’m going to make some notes about when we’re on our way. Al least when I’ve a place to connect to my computer.

Changes to the blog

Wed, 14 Jul 2004 02:04:52 +0200

As you can see my blog is powered by Bryar. It can be found on CPAN. I made some changes to Bryar that I liked. I’m not sure what to do with these changes. Should I give them back to the owner, or not? It’s more like a it works for me hack.

I added the following items to the software.

Wiki formatting using Text::KwikiFormatish
Separated datadir and entrydir.
Simple attr_accessor, attr_reader (like ruby) functions

These items are really nice to have I think. There is some other stuff that would be nice.

Emacs to the rescue

Wed, 14 Jul 2004 01:38:06 +0200

Now I’ve a blog, but it’s not easy to add an item. To make it somewhat easy, I have created an elisp functions in emacs to create an entry.

the elisp file

Mon, 01 Jan 0001 00:00:00 +0000

What can this plugin do?

Search

Mon, 01 Jan 0001 00:00:00 +0000

Settings

Mon, 01 Jan 0001 00:00:00 +0000

The plugin has three configuration options: token, author and title.

Sponsor

Mon, 01 Jan 0001 00:00:00 +0000