signal
======

POSIX specification: http://www.opengroup.org/onlinepubs/9699919799/functions/signal.html

Gnulib module: ---

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  * On System V platforms, when the signal is triggered, the kernel uninstalls the handler (i.e. resets the signal's action to SIG_DFL) before invoking the handler.  This opens the door to race conditions: undesired things happen if the signal is triggered twice and the signal handler was not quick enough reinstalling itself as a handler.  On BSD platforms and glibc platforms, on the other hand, when the signal is triggered, the kernel blocks the signal before invoking the handler.  This is saner, but POSIX still allows either behavior.  To avoid this problem, use sigaction instead of signal.