The internet needs groups

The internet needs groups! I'm not talking about the social entity like groups and individuals. I envision a net entity group like website, webpage, newsgroup or email address.
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Me on Twitter

I did not blog for 2 years. It's not that I did not try. I have about 8 unfinished drafts but somehow they are not so current anymore or would need a lot of work, so they are unlikely to ever appear. That's why I gave twitter a second try: @HenrykGerlach

I also included it in my blog's sidebar so visitors see I'm not dead yet. I don't really like their terms, though.

Using BioLux NV microscope in Ubuntu Linux

A human cell
I recently got a Bresser BioLux NV microscope. Of course it is quite cheap and you get what you pay for. I'm still very pleased with it because it is a fun toy, and I'm not afraid to destroy something by not treating it properly. I'm also happy that the cam works well with Linux.

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Ubuntu Linux 10.10 on Samsung NP-R540

Extreme Tuxracer with free ATI-Driver
I recently bought a cheap Samsung NP-R540 with an ATI Mobility Radeon HD 4500.
Ubuntu 10.10 installed smoothly. I encountered two problems:

  • The comercial ATI-video driver did not want to install, so I switched to
    the free driver and I'm happy since.
  • The Touchpad does not work well for me in multitouch-mode.

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True is False

Usually I prefer to rant about the oddities of ruby but this time it's python.
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Auto reload and poor man's http caching in PHP

I recently had a problem with my website Some not so nice fellow told his opera browser to reload a 300k page every 5 seconds, moved it to some tab and forgot about it for weeks. He caused 2 Gb of traffic per day. Time to implement some cache control.
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Automatic encryption of home directories using TrueCrypt 6.2a and pam_exec

This post describes how to encrypt the home directory of your users on GNU Linux with the help of TrueCrypt and PAM using the login-password as encryption key.
I wrote about Automatic encryption of home directories using TrueCrypt before. This time we'll use TrueCrypt 6.2a. Futhermore we'll use Ubuntu 9.04 Jaunty Jackalope and we replaced pam_mount by pam_exec. For convenience this post will be selfcontained (ie. I copy redundant parts from the old one).

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Usage of hg commit –date (mercurial)

Recently, I was trying to move some stuff from RCS to mercurial. There does not seem to exist a converter and since it was only a few revisions, I decided to do it by hand. The problem arose how to set the commit date manually and google yielded a nice blog post that answered my question (refering to the formidable but less searchable hgbook).
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Makefiles for LaTeX

This entry was originally submitted to Debian Package of the day, but rejected because make is well known.

A directed Graph: In connects to InterM that connects to Out
Figure 1:The file In is used to produce InterM that is itself
used to produce Out. Therefore Out depends directly on InterM and indirectly on In.

I agree that most programmers and administrators know GNU make. Sadly, it is ignored by most others. GNU make solves a very common problem that everyone faces when processing more than one file with more than one programm. It keeps track which file has been changed and which files have to be regenerated.

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Constantize in Python

Rails offers a nice function called constantize. It is easy to rebuild this (to some extend) in python. But the price is too high.
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