If you are on Linux, you can run your script under 'strace'. This will log signals received by the process as well as system calls made. If you don't want to see the syscalls, run strace -e trace=none perl yourscript.pl.

If you're on Solaris, then 'truss' will probably do the same job for you.

This is with a kill -CONT xxx being done in another window.

$ strace -e trace=none sleep 50
--- SIGCONT (Continued) @ 0 (0) ---
--- SIGCONT (Continued) @ 0 (0) ---
--- SIGCONT (Continued) @ 0 (0) ---
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