Exercise: Catch ctrl-c and ask continue or terminate?
Take the examples/advanced-perl/catch_ctr_c.pl and change it so when the user presses Ctrl-C the counting stops and the user is asked if she really wants to terminate the program. (y/n).
If yes is given then quit. If no is given continue.
If Ctrl-c is pressed again later then ask again.
Make sure you do as little as possible in the actual signal handle.