Mastering Linux Kernel Development

Waiting for queued signals

When applying signals for process communication, it might be more appropriate for a process to suspend itself until the occurrence of a specific signal, and resume execution on the arrival of a signal from another process. The POSIX calls sigsuspend(), sigwaitinfo(), and sigtimedwait() provide this functionality:

int sigsuspend(const sigset_t *mask);int sigwaitinfo(const sigset_t *set, siginfo_t *info);int sigtimedwait(const sigset_t *set, siginfo_t *info, const struct timespec *timeout);

While all of these APIs allow a process to wait for a specified signal to occur, sigwaitinfo() provides additional data about the signal through the siginfo_t instance returned through the info pointer. sigtimedwait() extends the ...