SlackBuildsOrg/development/check

Check is a unit test framework for C.  It features a simple interface for 
defining unit tests, putting little in the way of the developer.  Tests are 
run in a separate address space, so Check can catch both assertion failures 
and code errors that cause segmentation faults or other signals.  The output 
from unit tests can be used within source code editors and IDEs.

See the project's home page for more information, including a tutorial.