signal/sighold.c

   1 /* Add SIG to the calling process' signal mask.
   2    Copyright (C) 1998-2022 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #define __need_NULL
  20 #include <stddef.h>
  21 #include <signal.h>
  22
  23 int
  24 sighold (int sig)
  25 {
  26   sigset_t set;
  27
  28   sigemptyset (&set);
  29   if (sigaddset (&set, sig) < 0)
  30     return -1;
  31   return __sigprocmask (SIG_BLOCK, &set, NULL);
  32 }