sigsuspend(S)                  6 January 1993                  sigsuspend(S)


 Name

    sigsuspend - wait for signal(s)

 Syntax


    cc  . . .  -lc


    #include  <signal.h>

    int sigsuspend  (sigmask)
    sigset_t *sigmask;


 Description

    A call to the sigsuspend routine replaces the process's signal mask with
    the signal set to which the argument sigmask points.  The routine then
    suspends the process until it receives a signal whose associated action
    is to either terminate the process or execute a signal-catching function.

    If the action is to execute a signal-catching function, the sigsuspend
    routine returns immediately after the signal-catching function does.  The
    signal mask is restored to the value it held before the call to the sig-
    suspend routine.  If the action calls for the termination of the process,
    the sigsuspend routine does not return.

    As with all signal routines, un-ignorable signals cannot be blocked (see
    signal(S).  or sigaction(S)).  The system enforces this restriction
    without indicating an error.

 Return value

    Because the sigsuspend function suspends process execution indefinitely,
    no successful completion value is returned.  A value of -1 is returned
    and errno is set to indicate the error.

 Diagnostics

    If the following condition occurs, the sigsuspend function returns -1 and
    sets errno to the corresponding value:

    [EINTR]   A signal is caught by the calling process and control is
              returned from the signal-catching function.


 See also

    pause(S), sigaction(S), signal(S), sigpending(S), sigprocmask(S),
    sigset(S), sigsetjmp(S) sigsetv(S),

 Standards conformance

    sigsuspend is conformant with:
    IEEE POSIX Std 1003.1-1990 System Application Program Interface (API) [C
    Language] (ISO/IEC 9945-1);
    X/Open Portability Guide, Issue 3, 1989;
    and NIST FIPS 151-1.