bits/sigaction.h

   1 /* Copyright (C) 1991,92,96,97,98,2001 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #ifndef _SIGNAL_H
  20 # error "Never include <bits/sigaction.h> directly; use <signal.h> instead."
  21 #endif
  22
  23 /* These definitions match those used by the 4.4 BSD kernel.
  24    If the operating system has a `sigaction' system call that correctly
  25    implements the POSIX.1 behavior, there should be a system-dependent
  26    version of this file that defines `struct sigaction' and the `SA_*'
  27    constants appropriately.  */
  28
  29 /* Structure describing the action to be taken when a signal arrives.  */
  30 struct sigaction
  31   {
  32     /* Signal handler.  */
  33 #ifdef __USE_POSIX199309
  34     union
  35       {
  36         /* Used if SA_SIGINFO is not set.  */
  37         __sighandler_t sa_handler;
  38         /* Used if SA_SIGINFO is set.  */
  39         void (*sa_sigaction) (int, siginfo_t *, void *);
  40       }
  41     __sigaction_handler;
  42 # define sa_handler     __sigaction_handler.sa_handler
  43 # define sa_sigaction   __sigaction_handler.sa_sigaction
  44 #else
  45     __sighandler_t sa_handler;
  46 #endif
  47
  48     /* Additional set of signals to be blocked.  */
  49     __sigset_t sa_mask;
  50
  51     /* Special flags.  */
  52     int sa_flags;
  53   };
  54
  55 /* Bits in `sa_flags'.  */
  56 #if defined __USE_UNIX98 || defined __USE_MISC
  57 # define SA_ONSTACK     0x0001  /* Take signal on signal stack.  */
  58 # define SA_RESTART     0x0002  /* Restart syscall on signal return.  */
  59 # define SA_NODEFER     0x0010  /* Don't automatically block the signal when
  60                                     its handler is being executed.  */
  61 # define SA_RESETHAND   0x0004  /* Reset to SIG_DFL on entry to handler.  */
  62 #endif
  63 #define SA_NOCLDSTOP    0x0008  /* Don't send SIGCHLD when children stop.  */
  64
  65 #ifdef __USE_MISC
  66 # define SA_INTERRUPT   0       /* Historical no-op ("not SA_RESTART").  */
  67
  68 /* Some aliases for the SA_ constants.  */
  69 # define SA_NOMASK    SA_NODEFER
  70 # define SA_ONESHOT   SA_RESETHAND
  71 # define SA_STACK     SA_ONSTACK
  72 #endif
  73
  74
  75 /* Values for the HOW argument to `sigprocmask'.  */
  76 #define SIG_BLOCK       1       /* Block signals.  */
  77 #define SIG_UNBLOCK     2       /* Unblock signals.  */
  78 #define SIG_SETMASK     3       /* Set the set of blocked signals.  */