Examples, useful helper functions I rewrite over and over, small code snippets that might be useful, et cetera.
A major design goal of these is to have as few dependencies other than libc / standard UNIX system calls as possible to enable them to be rapidly integrated into many embedded systems.
Convert/serialize fixed width integer types to big-endian byte buffers. These are optimized for cross platform compatibility not for speed. The work is done entirely algebraically so it should work even on a crazy hypothetical middle endian machine that doesn't use twos-compliment encoding. Of course it can convert them back again as well.
This converts IEEE754 floats/doubles to integers preserving the maximum precision (the secret ingredient is frexp ) and then can serialize them further to big-endian byte buffers using the xplatform_endian functions above. The return trip to IEEE754 floats/doubles is also supported.
C implementation of a linked list holding arbitrary data. The grownup version of the kind of thing you wrote for yourself in your Programming II class once you realized you would need it for every project. It uses common conceits like iterators and contexts for loading up function pointers for comparing / allocating data the "class" knows nothing about.
The default C tokenizer strtok() is so awful that even its own man page recommended it be avoided for a time. This one uses a bit more memory, but it doesn't corrupt the input string, can be used on constant strings, and doesn't keep any state in hidden internal static variables making it much easier to make threadsafe.