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Articles about howto

  1. Inplace editing

    This article describes how to edit files in-place programmatically. This has been part of my toolbox for a long time, so I thought I’d document it here.

  2. Using sed

    As I’ve written about before (see engineering), I often use CalculiX for structural mechanics calculations of products made from composites. These often involve calculating lots of different combinations of materials, lay-ups and load cases. For convenience and for them being self-contained, each variant is usually in a different directory.

    So when I find an improvement to e.g. a pre.fbd, Makefile or job.inp, I want modify all of the other instances as well. This is where sed (which stands for “stream editor”) comes into play.

    date: 2022-05-22
    modified: 2022-08-31
    reading time: 5 min.
    category: howto
    tags: sed
  3. Merging local git repositories

    For a long time, I’ve had a directory ~/templates to store template files for several programs.

    For historical reasons, my LaTeX templates have been stored under ~/latex/templates.

    Both have been under git revision control since 2006; before that I used rcs.

    I want to merge both local repositories under ~/templates. This articla documents how that was done.

  4. Simple viewer for STEP files on UNIX

    The STEP format is probably the most used accurate 3D geometry exchange format. (It can contain a lot more than just geometry!)

    STL files (most often used in 3D printers) are based on triangles, which are basically only an approximation of the real geometry.

    A lot of available STEP-file viewer are windows-only. I’ve been looking for a simple STEP-file viewer for UNIX-like operating systems, so that I can see the parts that I’m making using cadquery (see also: cadquery documentation).

    I’m not a fan of IDE’s like cq-editor or IDE’s in general. In particular, cq-editor pulls in the whole of spyder (a Python IDE) just to get syntax highlighting in its built-in editor.

    date: 2021-11-04
    reading time: 2 min.
    category: howto
    tags: STEP
  5. De-facebook your internet

    Since I do not enjoy being a product for facebook to monetize, I’ve decided to de-facebook the internet, at least for me.

    This article assumes you’re running your own DNS server. The code in this article can generate configuration data for dnsmasq and unbound.

    The consumer versions os ms-windows don’t come with a DNS server, and most of the good ones do not run on it. If you are using ms-windows, I suggest using a pi-hole <https://pi-hole.net/> on your home network as a DNS server.

    date: 2021-10-22
    modified: 2021-12-04
    reading time: 3 min.
    category: howto
    tags: DNS
  6. Installing Openstreetmap data on a Garmin zūmo 340LM

    This documents how you can install openstreetmap data on the Garmin zūmo 340 LM. This procedure probably also works on other Garmin devices, but I haven’t tested that. The commands listed in this article assumes you’re using a UNIX-like operating system. While most of the actions could be performed on ms-windows, I haven’t run that in decades, so I’m not the person to give advice about that

  7. Making ringtones with free software tools

    Most smartphones come with a range of ringtones.

    But if you don’t like those, you can make them yourself from music that you are allowed to use.

    All software that is used here is free software. They should work on all recent UNIX-like operating systems. In my case, I installed all of these programs using the FreeBSD ports system.


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