SWI-Prolog catches the Unix signals SIGINT, SIGFPE and SIGSEGV. To avoid problems with foreign code attempting to catch these signals foreign code should call PL_signal() to install signal handlers rather than the Unix library function signal(). SWI-Prolog will always handle SIGINT itself. SIGFPE and SIGSEGV are passed to the foreign code handlers if Prolog did not expect that signal.
.BF .F void (*PL_signal(sig, func)) 0 This function should be used to install signal handlers rather than the Unix library function signal(). It ensures consistent signal handling between SWI-Prolog and the foreign code and reinstalls signal handlers if a state created with save_program/1 is restarted. .EF