Origin: https://bitbucket.org/erikedlund/libsetopt

Mirror: https://github.com/edlund/libsetopt

Warning: Since setopt is based on getopt(), it's not thread safe or reentrant. The API originally used a setopt state managed by the user, however, in order to avoid giving the wrong signals to developers, it's now using a single global state to look every bit as thread unsafe and non-reentrant as it is.

Compared to using only getopt(), setopt() can be a little harder to initially understand as it works through callbacks most often created through utility macros. Hopefully the resulting code will be more readable and more modular once one get used to it.

The basic idea is that setopt() will set values stored in a container (structure) of some sort based on options passed on the command line. Later, the values stored are validated, but it's possible to write custom callbacks that validates arguments before they're stored.