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I have a bunch of Raspberry Pi systems all over the place, goofy things that they are. They do dumb and annoying jobs in strange locations. I even have one of the older models, which is called just the B+. You can think of it as the "1B+" but apparently it was never officially branded the 1. If you have one of these, or perhaps an original Pi Zero hanging around, you might find that C++ programs b

Writing Software, technology, sysadmin war stories, and more. There are more than a few bear traps in the larger Unix environment that continue to catch people off-guard. One of the perennial favorites is thread safety, particularly as it applies to the environment manipulation functions under glibc. The usual warning is that if you run multiple threads, you'd best not call setenv, because if some

Writing Software, technology, sysadmin war stories, and more. While I don't go on the Orange Site any more, I still make enough trips through the larger space of similar sites to get some idea of what people are talking about. Last week, the topic of interest seemed to be YAML and how evil it is. I can't argue with that. Every time I've crossed paths with it, I've been irritated by both it and who

Yesterday's post about "pipefail" also involved some systems which treated an empty file as a valid file. This turns out to be surprisingly common. I think people might be shocked at exactly how much you can get away with, and how many different things will accept such a beast. One of the failure modes I used to see with certain package-based systems at a job with a large number of computers is th

Writing Software, technology, sysadmin war stories, and more. The Linux kernel has a neat little feature which lets you set up a "helper" to handle core dumps. This is a trick you can use to grab core files from a pipe instead of having them land on your disk. If you have a lot of poorly-behaved programs, you can then do some magic to make a decision about whether to keep the core or whether you c

Writing Software, technology, sysadmin war stories, and more. Ah, fork(). The way processes make more processes. Well, one of them, anyway. It seems I have another story to tell about it. It can fail. Got that? Are you taking this seriously? You should. fork can fail. Just like malloc, it can fail. Neither of them fail often, but when they do, you can't just ignore it. You have to do something int