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Passing file descriptors over Unix domain sockets

So you can send file descriptors over AF_UNIX sockets, easy right? It’s done by sendmsg/recvmsg calls, using the ancilliary data mechanism. Ok, the API is a bit cryptic when it comes to the ancilliary message data buffer (CMSG_ALIGN what?), but fairly usable. But consider a SOCK_STREAM socket. When am I going to receive the ancilliary data? Is it logically a separate stream? What happends on partial reads? What happends on partial sends?
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Flask file upload in 32-bit Debian Stretch

If you upgrade to 32-bit Debian stretch and suddenly file uploads start failing in your Flask applications, this is caused by a bug in mod_wsgi. Just grab a never package from debian testing (4.5.17 seems to be ok). The bug causes the application to produce “Bad Request” errors. I will affect anything based on Werkzeug and probably all mod_wsgi based applications. The bug is fixed in mod_wsgi commit 9192fd36620 and the patch is not in Stretch as of today.
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Thinkpad Coil Whine

ThinkPad Coil Whine Some ThinkPads have a slight coil whine, derived from the CPU load. Mine (T550) does. It is not really loud, but it can get annoying when working in quiet environment. The coil whine is caused by the processor entering and leaving its power-saving states. This causes a change in the current going into the processor and the power circuitry around it emits a noise (some people also suggest the processor itself makes such a noise).
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Star Micronics LC24-15 printer with CUPS

Introduction LC24-15 is a 24-dot matrix printer produced by Star Micronics in the late 80's. The company is still alive and you can even download the manual for LC24-15 and LC24-15 II from their site. With a few hacks, it is fairly usable even today. The printer is capable of priting text and graphics, with the highest available resolution being 360x180 DPI. It also offers various features, such as downloadable fonts, which are not really usefull today, since the text will be rendered on the computer and sent to the printer as graphics anyways.
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