sigsuspend(2)sigsuspend(2)NAMEsigsuspend - wait for a signal
The function replaces the current signal mask of the calling thread
with the set of signals pointed to by and then suspends the thread
until delivery of a signal whose action is either to execute a signal-
catching function or to terminate the process. This will not cause any
other signals that may have been pending on the process to become pend‐
ing on the thread.
If the action is to terminate the process then will never return. If
the action is to execute a signal-catching function, then will
return after the signal-catching function returns, with the signal mask
restored to the set that existed prior to the call.
It is not possible to block signals that cannot be ignored. This is
enforced by the system without causing an error to be indicated.
Since suspends thread execution indefinitely, there is no successful
completion return value. If a return occurs, −1 is returned and is set
to indicate the error.
The function will fail if:
A signal is caught by the calling process and control is
the signal-catching function.
sigmask points to an invalid address. The reliable
detection of this error is implementation-depen‐
Since blocked signal masks are maintained at the thread level, modifies
only the calling thread's blocked signal mask. suspends only the call‐
ing thread until it receives a signal.
If other threads in the process do not block the signal, the signal may
be delivered to another thread in the process and the thread in may
continue waiting. For this reason, the use of sigwait(2) is recom‐
mended instead of for multi-threaded applications.
For more information regarding signals and threads, refer to signal(5).
LWP (Lightweight Processes) Considerations
modifies only the calling LWP's signal mask and suspends only the call‐
ing LWP until receipt of a signal.
was derived from the IEEE POSIX 1003.1-1988 Standard.
SEE ALSOpause(2), sigaction(2), sigpending(2), sigprocmask(2), sigsetops(3C),
First released in Issue 3.
Entry included for alignment with the POSIX.1-1988 standard.