SIGSUSPEND(2)SIGSUSPEND(2)NAMEsigsuspend - install a signal mask and suspend caller until signal
int sigsuspend(const sigset_t *set);
The sigsuspend() function replaces the caller's signal mask with the
set of signals pointed to by the set argument and suspends the caller
until delivery of a signal whose action is either to execute a signal
catching function or to terminate the process. If the set argument
points to an invalid address, the behavior is undefined and errno may
be set to EFAULT.
If the action is to terminate the process, sigsuspend() does not
return. If the action is to execute a signal catching function, sig‐
suspend() returns after the signal catching function returns. On
return, the signal mask is restored to the set that existed before the
call to sigsuspend().
It is not possible to block signals that cannot be ignored (see sig‐
nal.h(3HEAD)). This restriction is silently imposed by the system.
Since sigsuspend() suspends the caller's execution indefinitely, there
is no successful completion return value. On failure, it returns −1 and
sets errno to indicate the error.
The sigsuspend() function will fail if:
A signal was caught by the caller and control was returned
from the signal catching function.
The sigsuspend() function may fail if:
The set argument points to an illegal address.
See attributes(5) for descriptions of the following attributes:
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
│Interface Stability │ Standard │
│MT-Level │ Async-Signal-Safe │
SEE ALSOsigaction(2), sigprocmask(2), sigwait(2), signal(3C), signal.h(3HEAD),
If the caller specifies more than one unblocked signal in the mask to
sigsuspend(), more than one signal might be processed before the call
to sigsuspend() returns.
While the caller is executing the signal handler that interrupted its
call to sigsuspend(), its signal mask is the one passed to sigsus‐
pend(), modified as usual by the signal mask specification in the sig‐
nal's sigaction(2) parameters. The caller's signal mask is not
restored to its previous value until the caller returns from all the
signal handlers that interrupted sigsuspend().
Jun 24, 2001 SIGSUSPEND(2)