[c] Parsing command-line arguments in C

Tooting my own horn if I may, I'd also like to suggest taking a look at an option parsing library that I've written: dropt.

  • It's a C library (with a C++ wrapper if desired).
  • It's lightweight.
  • It's extensible (custom argument types can be easily added and have equal footing with built-in argument types).
  • It should be very portable (it's written in standard C) with no dependencies (other than the C standard library).
  • It has a very unrestrictive license (zlib/libpng).

One feature that it offers that many others don't is the ability to override earlier options. For example, if you have a shell alias:

alias bar="foo --flag1 --flag2 --flag3"

and you want to use bar but with--flag1 disabled, it allows you to do:

bar --flag1=0