What are good libraries for C with datastructures like vectors, deques, stacks, hashmaps, treemaps, sets, etc.? Plain C, please, and platform-independent.
As always, Google is your friend:
http://nixbit.com/cat/programming/libraries/c-generic-library/
specifically:
http://nixbit.com/cat/programming/libraries/generic-data-structures-library/
The Glib library used on the Gnome project may also be some use. Moreover it is pretty well tested.
IBM developer works has a two part tutorial on its use: The wonders of GLib, Part 1, Part 2
There's some stuff in the Apache Portable Runtime (APR) that I'd expect to be very solid.
Maybe http://sglib.sourceforge.net/ if you want an easy to use, very fast, macro based library.
If hash tables, extensible strings and dynamic vector are enough for your needs, please have a look at the library I put toghether: http://code.google.com/p/c-libutl/.
I also would welcome any feedback!