signal/signal.h

   1 /* Copyright (C) 1991, 92, 93, 94, 95, 96 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 Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    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    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 /*
  20  *      ISO C Standard: 4.7 SIGNAL HANDLING <signal.h>
  21  */
  22
  23 #ifndef _SIGNAL_H
  24
  25 #if     !defined(__need_sig_atomic_t) && !defined(__need_sigset_t)
  26 #define _SIGNAL_H       1
  27 #include <features.h>
  28 #endif
  29
  30 __BEGIN_DECLS
  31
  32 #define  __need_size_t
  33 #include <stddef.h>
  34
  35 #include <gnu/types.h>
  36 #include <sigset.h>             /* __sigset_t, __sig_atomic_t.  */
  37
  38 #if     !defined(__sig_atomic_t_defined) &&     \
  39   (defined(_SIGNAL_H) || defined(__need_sig_atomic_t))
  40 /* An integral type that can be modified atomically, without the
  41    possibility of a signal arriving in the middle of the operation.  */
  42 typedef __sig_atomic_t sig_atomic_t;
  43 #endif /* `sig_atomic_t' undefined and <signal.h> or need `sig_atomic_t'.  */
  44 #undef  __need_sig_atomic_t
  45
  46 #ifdef  _SIGNAL_H
  47
  48 #include <signum.h>
  49
  50 /* Type of a signal handler.  */
  51 typedef void (*__sighandler_t) __P ((int));
  52
  53 /* Set the handler for the signal SIG to HANDLER,
  54    returning the old handler, or SIG_ERR on error.  */
  55 extern __sighandler_t signal __P ((int __sig, __sighandler_t __handler));
  56
  57 /* Send signal SIG to process number PID.  If PID is zero,
  58    send SIG to all processes in the current process's process group.
  59    If PID is < -1, send SIG to all processes in process group - PID.  */
  60 extern int __kill __P ((__pid_t __pid, int __sig));
  61 #ifdef  __USE_POSIX
  62 extern int kill __P ((__pid_t __pid, int __sig));
  63 #endif /* Use POSIX.  */
  64
  65 #if defined(__USE_BSD) || defined(__USE_XOPEN_EXTENDED)
  66 /* Send SIG to all processes in process group PGRP.
  67    If PGRP is zero, send SIG to all processes in
  68    the current process's process group.  */
  69 extern int killpg __P ((__pid_t __pgrp, int __sig));
  70 #endif /* Use BSD || X/Open Unix.  */
  71
  72 /* Raise signal SIG, i.e., send SIG to yourself.  */
  73 extern int raise __P ((int __sig));
  74
  75 #ifdef  __USE_SVID
  76 /* SVID names for the same things.  */
  77 extern __sighandler_t ssignal __P ((int __sig, __sighandler_t __handler));
  78 extern int gsignal __P ((int __sig));
  79 #endif /* Use SVID.  */
  80
  81 #ifdef  __USE_MISC
  82 /* Print a message describing the meaning of the given signal number.  */
  83 extern void psignal __P ((int __sig, __const char *__s));
  84 #endif /* Use misc.  */
  85
  86
  87 /* Block signals in MASK, returning the old mask.  */
  88 extern int __sigblock __P ((int __mask));
  89
  90 /* Set the mask of blocked signals to MASK, returning the old mask.  */
  91 extern int __sigsetmask __P ((int __mask));
  92
  93 /* Set the mask of blocked signals to MASK,
  94    wait for a signal to arrive, and then restore the mask.  */
  95 extern int __sigpause __P ((int __mask));
  96
  97 #ifdef  __USE_BSD
  98 #define sigmask(sig)    __sigmask(sig)
  99
 100 extern int sigblock __P ((int __mask));
 101 extern int sigsetmask __P ((int __mask));
 102 extern int sigpause __P ((int __mask));
 103
 104 /* This function is here only for compatibility.
 105    Use `sigprocmask' instead.  */
 106 extern int siggetmask __P ((void));
 107 #endif /* Use BSD.  */
 108
 109
 110 #ifdef  __USE_MISC
 111 #define NSIG    _NSIG
 112 #endif
 113
 114 #ifdef  __USE_GNU
 115 typedef __sighandler_t sighandler_t;
 116 #endif
 117
 118 /* 4.4 BSD uses the name `sig_t' for this.  */
 119 #ifdef  __USE_BSD
 120 typedef __sighandler_t sig_t;
 121 #endif
 122
 123 #endif /* <signal.h> included.  */
 124
 125
 126 #ifdef  __USE_POSIX
 127
 128 #if     !defined(__sigset_t_defined) && \
 129    (defined(_SIGNAL_H) || defined(__need_sigset_t))
 130 typedef __sigset_t sigset_t;
 131 #define __sigset_t_defined      1
 132 #endif /* `sigset_t' not defined and <signal.h> or need `sigset_t'.  */
 133 #undef  __need_sigset_t
 134
 135 #ifdef  _SIGNAL_H
 136
 137 /* Clear all signals from SET.  */
 138 extern int sigemptyset __P ((sigset_t *__set));
 139
 140 /* Set all signals in SET.  */
 141 extern int sigfillset __P ((sigset_t *__set));
 142
 143 /* Add SIGNO to SET.  */
 144 extern int sigaddset __P ((sigset_t *__set, int __signo));
 145
 146 /* Remove SIGNO from SET.  */
 147 extern int sigdelset __P ((sigset_t *__set, int __signo));
 148
 149 /* Return 1 if SIGNO is in SET, 0 if not.  */
 150 extern int sigismember __P ((__const sigset_t *__set, int signo));
 151
 152 #ifdef  __OPTIMIZE__
 153 /* <sigset.h> defines the __ versions as macros that do the work.  */
 154 #define sigemptyset(set)        __sigemptyset(set)
 155 #define sigfillset(set)         __sigfillset(set)
 156 #define sigaddset(set, signo)   __sigaddset(set, signo)
 157 #define sigdelset(set, signo)   __sigdelset(set, signo)
 158 #define sigismember(set, signo) __sigismember(set, signo)
 159 #endif
 160
 161 /* Get the system-specific definitions of `struct sigaction'
 162    and the `SA_*' and `SIG_*'. constants.  */
 163 #include <sigaction.h>
 164
 165 /* Get and/or change the set of blocked signals.  */
 166 extern int __sigprocmask __P ((int __how,
 167                                __const sigset_t *__set, sigset_t *__oset));
 168 extern int sigprocmask __P ((int __how,
 169                              __const sigset_t *__set, sigset_t *__oset));
 170
 171 /* Change the set of blocked signals to SET,
 172    wait until a signal arrives, and restore the set of blocked signals.  */
 173 extern int sigsuspend __P ((__const sigset_t *__set));
 174
 175 /* Get and/or set the action for signal SIG.  */
 176 extern int __sigaction __P ((int __sig, __const struct sigaction *__act,
 177                              struct sigaction *__oact));
 178 extern int sigaction __P ((int __sig, __const struct sigaction *__act,
 179                            struct sigaction *__oact));
 180
 181 /* Put in SET all signals that are blocked and waiting to be delivered.  */
 182 extern int sigpending __P ((sigset_t *__set));
 183
 184
 185 /* Select any of pending signals from SET or wait for any to arrive.  */
 186 extern int __sigwait __P ((__const sigset_t *__set, int *__sig));
 187 extern int sigwait __P ((__const sigset_t *__set, int *__sig));
 188
 189 #endif /* <signal.h> included.  */
 190
 191 #endif /* Use POSIX.  */
 192
 193 #if     defined(_SIGNAL_H) && defined(__USE_BSD)
 194
 195 /* Names of the signals.  This variable exists only for compatiblity.
 196    Use `strsignal' instead (see <string.h>).  */
 197 extern __const char *__const _sys_siglist[NSIG];
 198 extern __const char *__const sys_siglist[NSIG];
 199
 200 /* Structure passed to `sigvec'.  */
 201 struct sigvec
 202   {
 203     __sighandler_t sv_handler;  /* Signal handler.  */
 204     int sv_mask;                /* Mask of signals to be blocked.  */
 205
 206     int sv_flags;               /* Flags (see below).  */
 207 #define sv_onstack      sv_flags /* 4.2 BSD compatibility.  */
 208   };
 209
 210 /* Bits in `sv_flags'.  */
 211 #define SV_ONSTACK      (1 << 0)/* Take the signal on the signal stack.  */
 212 #define SV_INTERRUPT    (1 << 1)/* Do not restart system calls.  */
 213 #define SV_RESETHAND    (1 << 2)/* Reset handler to SIG_DFL on receipt.  */
 214
 215
 216 /* If VEC is non-NULL, set the handler for SIG to the `sv_handler' member
 217    of VEC.  The signals in `sv_mask' will be blocked while the handler runs.
 218    If the SV_RESETHAND bit is set in `sv_flags', the handler for SIG will be
 219    reset to SIG_DFL before `sv_handler' is entered.  If OVEC is non-NULL,
 220    it is filled in with the old information for SIG.  */
 221 extern int __sigvec __P ((int __sig, __const struct sigvec *__vec,
 222                           struct sigvec *__ovec));
 223 extern int sigvec __P ((int __sig, __const struct sigvec *__vec,
 224                         struct sigvec *__ovec));
 225
 226
 227 /* Get machine-dependent `struct sigcontext' and signal subcodes.  */
 228 #include <sigcontext.h>
 229
 230 /* Restore the state saved in SCP.  */
 231 extern int __sigreturn __P ((struct sigcontext *__scp));
 232 extern int sigreturn __P ((struct sigcontext *__scp));
 233
 234 #endif /* signal.h included and use BSD.  */
 235
 236
 237 #if defined(_SIGNAL_H) && (defined(__USE_BSD) || defined(__USE_XOPEN_EXTENDED))
 238
 239 /* If INTERRUPT is nonzero, make signal SIG interrupt system calls
 240    (causing them to fail with EINTR); if INTERRUPT is zero, make system
 241    calls be restarted after signal SIG.  */
 242 extern int siginterrupt __P ((int __sig, int __interrupt));
 243
 244
 245 /* Structure describing a signal stack.  */
 246 struct sigstack
 247   {
 248     __ptr_t ss_sp;              /* Signal stack pointer.  */
 249     int ss_onstack;             /* Nonzero if executing on this stack.  */
 250   };
 251
 252 /* Run signals handlers on the stack specified by SS (if not NULL).
 253    If OSS is not NULL, it is filled in with the old signal stack status.  */
 254 extern int sigstack __P ((__const struct sigstack *__ss,
 255                           struct sigstack *__oss));
 256
 257 /* Alternate interface.  */
 258 struct sigaltstack
 259   {
 260     __ptr_t ss_sp;
 261     size_t ss_size;
 262     int ss_flags;
 263   };
 264
 265 extern int sigaltstack __P ((__const struct sigaltstack *__ss,
 266                              struct sigaltstack *__oss));
 267
 268 #endif /* signal.h included and use BSD or X/Open Unix.  */
 269
 270 __END_DECLS
 271
 272 #endif /* signal.h  */