Welcome

This is my home in the virtual world, where I write about things that I want to share. The freely available software that I've written as well as some of the photographs I've taken over the years can also be found here. Please use the navigation links on the right if you are looking for something.

Recent articles

1. My e-mail setup

   For years I’ve been using fetchmail and procmail for incoming mail. However, both of these programs haven’t been maintained for years. So it was time to change.

2. Luminous clouds

   My balcony gets the evening sun. Sometimes the sun and clouds make for a stunning view. See below.

3. A simple feed reader for Youtube

   As an exercise, I wrote a small script to read the Atom feeds for some favourite youtube channels. Of course I could have installed a “real” feed-reader, but that would be overkill and not half as much fun. :-)

4. Attempting a conky replacement in Python (part 2)

   In part 1 we say that a simple replacement for conky for generating a statusline for i3 can be achieved. But since it uses the subprocess module to call external programs it is pretty CPU intensive.

   The question now is if we can reduce that? For that we’re going to use mmap to look at the mailbox, and call sysctlbyname(3) using ctypes to get the remaining system information. Note that sysctl et al and the names used are specific to FreeBSD.

5. Attempting a conky replacement in Python (part 1)

   My window manager (i3) has a small bar on the bottom of the screen. I use conky to put a single line of (text) information there.

6. Setting the Razer ornata chroma color from userspace

   This documents how to set the (static) color on this keyboard from user space using libusb (built into FreeBSD) and pyusb.

7. Automating package updates on FreeBSD

   When updating my ports, I prefer to use packages when I have not changed the options of a port. This describes how I do that.

8. Adding text or graphics to a PDF file (again)

   In an earlier article I talked about using a picture environment in LaTeX to add lines and text over an image. In another article I showed how to draw with PostScript, including using Encapsulated PostScript to include arbitrary images.

   In this article I want to cover the pros and cons of these methods and introduce a third method: TikZ.

9. ImageMagick: convert vs Wand

   The ImageMagick suite has been in my software toolbox for years. It is my go-to tool for manipulating bitmap images. Over the years I have written several front-ends for specific tasks for in Python.

   In general, I have used the subprocess module to launch convert or mogrify from Python.

   With the release of Wand 0.5.0 which supports ImageMagick 7, I decided to try that by porting one of my scripts (foto4lb) to it.

10. Installing Pelican 4

    Pelican is the static site generator that I use for my website. This allows me to write my website posts in almost plain text (actually a light-weight markup language named reStructuredText), which are then translated into HTML. As someone who has written his webpages in HTML by hand, I can tell you that this is definitely an improvement.

    Although I use LaTeX for things that require high-quality typesetting, these days almost all my other writings are in reStructuredText.

    The previous pelican version 3.7 was basically the last Python 2.7 application that I use. So now that pelican supports Python 3, I’m switching. Since Pelican 4 is not in the FreeBSD ports tree yet, I’m installing it myself.

    Note

    As of 4.0.1, Pelican is now in the FreeBSD ports tree and I’m using the port www/py-pelican.