Why would a kill -2 not work?

[Peter Steele]

>The amount of stuff you're allowed to do safely in a signal handler is 
>pretty minimal-- you're better off setting a flag, returning from the 
>signal handler, and having the next run past the main event loop or 
>whatever check for the flag and handle things in a normal app 
>context. If you try to do anything involving malloc() or s/printf, 
>etc, you're running risks. "man sigaction" is likely to be 
>informative.... 

This is basically what we doing. When the handler is triggered we set a global variable to indicate the system is shutting down. I also signal a condition to wake up a sleeping thread. The lack of log messages indicate that this handler never gets called and the system carries on as if the kill -2 never happened.