5 POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/signal.html}
9 Portability problems fixed by Gnulib:
13 Portability problems not fixed by Gnulib:
16 On System V platforms, when the signal is triggered, the kernel uninstalls the
17 handler (i.e.@: resets the signal's action to SIG_DFL) before invoking the
18 handler. This opens the door to race conditions: undesired things happen
19 if the signal is triggered twice and the signal handler was not quick enough
20 reinstalling itself as a handler. On BSD platforms and glibc platforms, on the
21 other hand, when the signal is triggered, the kernel blocks the signal
22 before invoking the handler. This is saner, but POSIX still allows either
23 behavior. To avoid this problem, use @code{sigaction} instead of