I was trying to do some TDD with CUnit and Emacs, but I was a bit disappointed at how painful it was to run the tests; save file, make, change to terminal and run. After configuring Emacs to save the file automatically I got rid of one step, but changing to the terminal window wall still a pain.

Then I thought of googling notify on file change, and I found inotify-tools, which enabled me to write this little script:

#!/bin/sh
while [ true ]
do inotifywait *.c
    gcc -g obj2gl.c -lcunit && ./a.out
done

So all I have to do now is save my file in Emacs, and the script runs the unit tests instantly.