This file is trap.def, from which is created trap.c.
It implements the builtin "trap" in Bash.
-Copyright (C) 1987-2004 Free Software Foundation, Inc.
+Copyright (C) 1987-2009 Free Software Foundation, Inc.
This file is part of GNU Bash, the Bourne Again SHell.
-Bash is free software; you can redistribute it and/or modify it under
-the terms of the GNU General Public License as published by the Free
-Software Foundation; either version 2, or (at your option) any later
-version.
+Bash is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
-Bash is distributed in the hope that it will be useful, but WITHOUT ANY
-WARRANTY; without even the implied warranty of MERCHANTABILITY or
-FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
-for more details.
+Bash is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
-You should have received a copy of the GNU General Public License along
-with Bash; see the file COPYING. If not, write to the Free Software
-Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA.
+You should have received a copy of the GNU General Public License
+along with Bash. If not, see <http://www.gnu.org/licenses/>.
$PRODUCES trap.c
$BUILTIN trap
$FUNCTION trap_builtin
$SHORT_DOC trap [-lp] [[arg] signal_spec ...]
-The command ARG is to be read and executed when the shell receives
+Trap signals and other events.
+
+Defines and activates handlers to be run when the shell receives signals
+or other conditions.
+
+ARG is a command to be read and executed when the shell receives the
signal(s) SIGNAL_SPEC. If ARG is absent (and a single SIGNAL_SPEC
is supplied) or `-', each specified signal is reset to its original
value. If ARG is the null string each SIGNAL_SPEC is ignored by the
-shell and by the commands it invokes. If a SIGNAL_SPEC is EXIT (0)
-the command ARG is executed on exit from the shell. If a SIGNAL_SPEC
-is DEBUG, ARG is executed after every simple command. If the`-p' option
-is supplied then the trap commands associated with each SIGNAL_SPEC are
-displayed. If no arguments are supplied or if only `-p' is given, trap
-prints the list of commands associated with each signal. Each SIGNAL_SPEC
-is either a signal name in <signal.h> or a signal number. Signal names
-are case insensitive and the SIG prefix is optional. `trap -l' prints
-a list of signal names and their corresponding numbers. Note that a
-signal can be sent to the shell with "kill -signal $$".
+shell and by the commands it invokes.
+
+If a SIGNAL_SPEC is EXIT (0) ARG is executed on exit from the shell. If
+a SIGNAL_SPEC is DEBUG, ARG is executed before every simple command.
+
+If no arguments are supplied, trap prints the list of commands associated
+with each signal.
+
+Options:
+ -l print a list of signal names and their corresponding numbers
+ -p display the trap commands associated with each SIGNAL_SPEC
+
+Each SIGNAL_SPEC is either a signal name in <signal.h> or a signal number.
+Signal names are case insensitive and the SIG prefix is optional. A
+signal may be sent to the shell with "kill -signal $$".
+
+Exit Status:
+Returns success unless a SIGSPEC is invalid or an invalid option is given.
$END
#include <config.h>
opt = DSIG_NOCASE|DSIG_SIGPREFIX; /* flags for decode_signal */
if (list_signal_names)
- return (display_signal_list ((WORD_LIST *)NULL, 1));
+ return (sh_chkwrite (display_signal_list ((WORD_LIST *)NULL, 1)));
else if (display || list == 0)
- return (display_traps (list));
+ return (sh_chkwrite (display_traps (list)));
else
{
char *first_arg;
- int operation, sig;
+ int operation, sig, first_signal;
operation = SET;
first_arg = list->word->word;
+ first_signal = first_arg && *first_arg && all_digits (first_arg) && signal_object_p (first_arg, opt);
+
+ /* Backwards compatibility. XXX - question about whether or not we
+ should throw an error if an all-digit argument doesn't correspond
+ to a valid signal number (e.g., if it's `50' on a system with only
+ 32 signals). */
+ if (first_signal)
+ operation = REVERT;
/* When in posix mode, the historical behavior of looking for a
missing first argument is disabled. To revert to the original
signal handling disposition, use `-' as the first argument. */
- if (posixly_correct == 0 && first_arg && *first_arg &&
+ else if (posixly_correct == 0 && first_arg && *first_arg &&
(*first_arg != '-' || first_arg[1]) &&
signal_object_p (first_arg, opt) && list->next == 0)
operation = REVERT;
if (interactive)
set_signal_handler (SIGINT, sigint_sighandler);
else
- set_signal_handler (SIGINT, termination_unwind_protect);
+ set_signal_handler (SIGINT, termsig_sighandler);
break;
case SIGQUIT:
char *t, *p, *sn;
p = trap_list[i];
-
if (p == (char *)DEFAULT_SIG)
return;