"C Unleashed" was written by Richard Heathfield, Lawrence Kirby and several other collaborators and published by SAMS in 2000. It's a really good book with lots of high-quality C code for various programming tasks.
It comes with a CD-ROM of the book's complete source code. While looking for
this code online recently, I could not find it, though from archived
comp.lang.c posts it was apparent that the authors made the code publicly
available. The main author's website at http://www.cpax.org.uk/ was supposed to
host it, but this website is down now. I also ran into sites that offer to
purchase this code, which was pretty annoying since it was originally offered
for free.
So I dug up my copy of the book and my trusty external CD reader and copied the code from the book's CD-ROM into this repository (it's remarkable how smoothly it worked on a 20-year-old CD-ROM).
This code is presented as-is, along with its original license (GPL as mentioned in the comment headers of the source files).
Hope others find this useful! If you believe that this repository is infringing someone's rights by existing, please get in touch.