sigsuspend()

Replace the signal mask, and then suspend the thread

Synopsis:

#include <signal.h>

int sigsuspend( const sigset_t *sigmask );

Arguments:

sigmask: A pointer to a sigset_t object that specifies the signals that you want in the thread's signal mask.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

The sigsuspend() function replaces the thread's signal mask with the set of signals pointed to by sigmask and then suspends the thread until delivery of a signal whose action is either to execute a signal-catching function (then return), or to terminate the thread.

Returns:

-1 (if the function returns); errno is set.

Errors:

EFAULT: A fault occurred trying to access the buffers provided.
EINTR: A signal was caught by the calling thread, and control is returned from the signal-catching function.

Examples:

/*
 * This program pauses until a signal other than
 * a SIGINT occurs. In this case a SIGALRM.
 */
#include <stdio.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>

sigset_t    set;

int main( void )
  {
    sigemptyset( &set );
    sigaddset( &set, SIGINT );

    printf( "Program suspended and immune to breaks.\n" );
    printf( "A SIGALRM will terminate the program"
        " in 10 seconds.\n" );
    alarm( 10 );
    sigsuspend( &set );
    return( EXIT_SUCCESS );
  }

Classification:

POSIX 1003.1

Safety:
Cancellation point	Yes
Interrupt handler	No
Signal handler	Yes
Thread	Yes