PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       sigaddset — add a signal to a signal set

SYNOPSIS

       #include <signal.h>

       int sigaddset(sigset_t *set, int signo);

DESCRIPTION

       The  sigaddset()  function adds the individual signal specified by the signo to the signal set pointed to
       by set.

       Applications shall call either sigemptyset() or sigfillset() at  least  once  for  each  object  of  type
       sigset_t  prior to any other use of that object. If such an object is not initialized in this way, but is
       nonetheless supplied as an argument to any of pthread_sigmask(), sigaction(),  sigaddset(),  sigdelset(),
       sigismember(),  sigpending(),  sigprocmask(),  sigsuspend(), sigtimedwait(), sigwait(), or sigwaitinfo(),
       the results are undefined.

RETURN VALUE

       Upon successful completion, sigaddset() shall return 0; otherwise, it shall return −1 and  set  errno  to
       indicate the error.

ERRORS

       The sigaddset() function may fail if:

       EINVAL The value of the signo argument is an invalid or unsupported signal number.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       Section  2.4,  Signal Concepts, pthread_sigmask(), sigaction(), sigdelset(), sigemptyset(), sigfillset(),
       sigismember(), sigpending(), sigsuspend()

       The Base Definitions volume of POSIX.1‐2008, <signal.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers,  Inc
       and  The  Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the event
       of any discrepancy between this version and the original IEEE and The Open Group Standard,  the  original
       IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at
       http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most likely to have  been  introduced
       during   the   conversion  of  the  source  files  to  man  page  format.  To  report  such  errors,  see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .