Yann "Bug" Dubois

If you need to configure exim4 on a web-server to route outgoing mail but do not want the web server to perform local delivery of e-mail addressed to your own domain name, the simplest way is to configure a “hubbed host” for your local domain. This will route all e-mails to your local domain through an external mail exchanger, and disable local delivery of e-mail to your own domain. And avoids the dreadful “Unrouteable address” error message.

Great news for all users of the very popular (70,000 downloads) legacy plugin for WordPress “YD Recent Posts Widgets with Thumbnails” that I developped in 2009 and maintained up to ca. 2011. This plugin now has an official, brand new successor known as “WP Frontpage News“.

The PHP language can be used to remote-control an actual web-browser on a server, to allow server-side scripting of complex web interactions involving for example Javascript of Flash-enabled content. This is a very powerful context, but it is tricky to setup. In addition, a proxy such as Squid can be used to log all http interactions, and can be used as an in-depth traffic analysis or debugging tool. This environment can be used for automated web debugging, continuous integration, unit-testing based web development, non-regression testing, load tests, automated screenshots, etc. Here is a quick setup memo for a running environment under Debian Linux (headless server).

Here is a quick and very simple way to calculate all linear component specifications of a LM 555 type timer IC chip based astable oscillator electronic circuit. This will give you resulting frequencies and pulse width for different resistor and capacitor values arranged in the provided classic circuit diagram.

Wear and tear have finally overcome. This Canon Powershot G10 has a stuck lens, and the warranty has long expired. I decided to take it apart to see if there is something to be done about it. I took some photographs of the tear-down process, and here is a detailed inside view of the camera.

Here is a short memo that I use for quickly reinstalling an operational configuration under Debian / Apache2 / PHP5 / Mysql for hosting web sites on a dedicated GNU/Linux hosted server. This configuration also includes eAccelerator and basic supervision and administration tools (Munin, phpsysinfo, mtop, PhpmyAdmin, AWStats). It is directly operational and sufficiently secured for a standard install (as long as packages are regularly updated). Anyways it works for me©®™.

Any serious hobbyist-grade two-channel digital oscilloscope is worth a few hundred bucks, with professional lab models reaching into the few thousands. One way to avoid spending too much on such a versatile equipment is to use a personal desktop or laptop computer as a digital oscilloscope. Commercially available plug-and-play probing interfaces and compatible software and drivers are still quite an expensive option. Alternatively, here is a way to turn any GNU/Linux computer with an integrated sound board into a free digital oscilloscope using free software and custom-built probes. Just follow this step-by-step visual guide.

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