HP 3000 Manuals HP 3000 Manuals
sigsuspend
Replaces the calling process's signal mask and suspends the calling
process to wait for a signal.
Syntax
#include <signal.h>
int sigsuspend (sigset_t *sigmask);
Parameters
sigmask If not NULL, a pointer to a structure of type sigset_t that
contains a new signal mask to be installed before suspending
the calling process. If NULL, the process's current signal
mask is used.
Return Values
No return Because sigsuspend() suspends process execution indefinitely,
there is no return value indicating success.
-1 An error occurred, and errno is set to indicate the error
condition.
Description
The sigsuspend() function replaces the calling process's signal mask with
the set of signals pointed to by sigmask. It then suspends the process
until the delivery of a signal whose action is either to execute a
signal-handling function (signal handler) or to terminate the process.
If the action is to execute a signal handler, upon completion of the
signal handler, sigsuspend() returns and restores the process's previous
signal mask. If the signal action is to terminate the process,
sigsuspend() does not return.
It is not possible to block the signals SIGKILL and SIGSTOP. If specified
in the structure pointed to by sigmask, they are removed by the system
without error.
Implementation Considerations
Refer to the EFAULT error description below.
If the sigmask parameter of the sigsuspend() function is set to NULL, the
process is suspended with the current signal mask. This implementation
is considered an extension to the POSIX.1 standard. A strictly
conforming POSIX application should pass in the sigmask parameter of the
sigsuspend() function the current signal mask returned by a successful
call to sigprocmask() where set is set to NULL.
Errors
If an error occurs, errno is set to one of the following values:
EFAULT CAUSE The system detected a bad address in attempting to
use the sigmask parameter.
ACTION Make sure that the pointer is correctly initialized.
EINTR CAUSE A signal was caught by the process, and control was
returned from a signal-handling function.
ACTION No action required.
See Also
pause(), sigaction(), sigpending(), sigprocmask(), <signal.h>, POSIX.1
(Section 3.3.7)