Unix to Windows Porting Dictionary for HPC

header file: signal.h

int sigdelset(sigset_t *set, int signo);

Header file: none

The sigdelset call removes the individual signal specified from the signal set pointed to by set.

The POSIX implementation of signals includes the ability to mask individual signals. A signal mask is maintained by the operating system for each process in the system. The sigdelset routine allows the user to conveniently maintain a copy of the processes mask so it can be applied to the system copy with a single call (sigprocmask()).

The Windows implementation of signals does not include a mask capability at the process level. To get around this limitation the user can implement masking in the handler itself after setting the handler up to accept all signals. Once the handler is invoked, it can inspect the number of the signal that has invoked it and decide whether to ignore it, process it or send it off to the default handler for that signal.

The sigdelset() call can be simulated by setting the action of signo entry in the signalmask array to either SIG_DFL or USER depending on current needs.