sigsuspend(2) System Calls Manual sigsuspend(2)
NAME
sigsuspend - wait for a signal
SYNOPSIS
DESCRIPTION
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 pending 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.
RETURN VALUE
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.
ERRORS
The function will fail if:
A signal is caught by the calling process and control is returned from
the signal-catching function.
sigmask points to an invalid address. The reliable detection of this error is implementation-dependent.
APPLICATION USAGE
Threads Considerations
Since blocked signal masks are maintained at the thread level, modifies only the calling thread's blocked signal mask. suspends only the
calling 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 recommended 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 calling LWP until receipt of a signal.
AUTHOR
was derived from the IEEE POSIX 1003.1-1988 Standard.
SEE ALSO
pause(2), sigaction(2), sigpending(2), sigprocmask(2), sigsetops(3C), sigwait(2), signal(5).
CHANGE HISTORY
First released in Issue 3.
Entry included for alignment with the POSIX.1-1988 standard.
STANDARDS CONFORMANCE
sigsuspend(2)
