$BUILTIN trap
$FUNCTION trap_builtin
-$SHORT_DOC trap [arg] [signal_spec]
+$SHORT_DOC trap [arg] [signal_spec] or trap -l
The command ARG is to be read and executed when the shell receives
signal(s) SIGNAL_SPEC. If ARG is absent all specified signals are
-reset to their original values. If ARG is the null string this
-signal is ignored by the shell and by the commands it invokes. If
-SIGNAL_SPEC is EXIT (0) the command ARG is executed on exit from
-the shell. The trap command with no arguments prints the list of
-commands associated with each signal number. SIGNAL_SPEC is either
-a signal name in <signal.h>, or a signal number. The syntax `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 $$".
+reset to their original values. If ARG is the null string each
+SIGNAL_SPEC is ignored by the shell and by the commands it invokes.
+If SIGNAL_SPEC is EXIT (0) the command ARG is executed on exit from
+the shell. If SIGNAL_SPEC is DEBUG, ARG is executed after every
+command. If ARG is `-p' then the trap commands associated with
+each SIGNAL_SPEC are displayed. If no arguments are supplied or if
+only `-p' is given, trap prints the list of commands associated with
+each signal number. SIGNAL_SPEC is either a signal name in <signal.h>
+or a signal number. `trap -l' prints a list of signal names and their
+corresponding numbers. Note that a signal can be sent to the shell
+with "kill -signal $$".
$END
-#include <sys/types.h>
+#include <config.h>
+
+#if defined (HAVE_UNISTD_H)
+# include <unistd.h>
+#endif
+
+#include "../bashtypes.h"
#include <signal.h>
+#include <stdio.h>
+#include "../bashansi.h"
+
#include "../shell.h"
#include "../trap.h"
#include "common.h"
+#include "bashgetopt.h"
+
+static int display_traps ();
/* The trap command:
trap <arg> <signal ...>
trap <signal ...>
trap -l
+ trap -p [sigspec ...]
trap [--]
Set things up so that ARG is executed when SIGNAL(s) N is recieved.
extern int interactive;
+int
trap_builtin (list)
WORD_LIST *list;
{
- register int i;
- int list_signal_names = 0;
+ int list_signal_names, display, result, opt;
- while (list)
+ list_signal_names = display = 0;
+ result = EXECUTION_SUCCESS;
+ reset_internal_getopt ();
+ while ((opt = internal_getopt (list, "lp")) != -1)
{
- if (ISOPTION (list->word->word, 'l'))
+ switch (opt)
{
+ case 'l':
list_signal_names++;
- list = list->next;
- }
- else if (ISOPTION (list->word->word, '-'))
- {
- list = list->next;
break;
- }
- else if ((*list->word->word == '-') && list->word->word[1])
- {
- bad_option (list->word->word);
- builtin_error ("usage: trap [-l] [arg] [sigspec]");
+ case 'p':
+ display++;
+ break;
+ default:
+ builtin_usage ();
return (EX_USAGE);
}
- else
- break;
}
+ list = loptend;
if (list_signal_names)
+ return (display_signal_list ((WORD_LIST *)NULL, 1));
+ else if (display || list == 0)
+ return (display_traps (list));
+ else
{
- int column = 0;
-
- for (i = 0; i < NSIG; i++)
- {
- printf ("%2d) %s", i, signal_name (i));
- if (++column < 4)
- printf ("\t");
- else
- {
- printf ("\n");
- column = 0;
- }
- }
- if (column != 0)
- printf ("\n");
- return (EXECUTION_SUCCESS);
- }
+ char *first_arg;
+ int operation, sig;
- if (list)
- {
- char *first_arg = list->word->word;
- int operation = SET, any_failed = 0;
-
- if (signal_object_p (first_arg))
+ operation = SET;
+ first_arg = list->word->word;
+ if (first_arg && *first_arg && signal_object_p (first_arg))
operation = REVERT;
else
{
while (list)
{
- int sig;
-
sig = decode_signal (list->word->word);
if (sig == NO_SIG)
{
builtin_error ("%s: not a signal specification",
list->word->word);
- any_failed++;
+ result = EXECUTION_FAILURE;
}
else
{
}
list = list->next;
}
- return ((!any_failed) ? EXECUTION_SUCCESS : EXECUTION_FAILURE);
}
- for (i = 0; i < NSIG; i++)
- {
- char *t, *p;
+ return (result);
+}
+
+static void
+showtrap (i)
+ int i;
+{
+ char *t, *p;
+
+ p = trap_list[i];
+
+ if (p == (char *)DEFAULT_SIG)
+ return;
+
+ t = (p == (char *)IGNORE_SIG) ? (char *)NULL : single_quote (p);
+ printf ("trap -- %s %s\n", t ? t : "''", signal_name (i));
+ if (t)
+ free (t);
+}
- p = trap_list[i];
+static int
+display_traps (list)
+ WORD_LIST *list;
+{
+ int result, i;
- if (p == (char *)DEFAULT_SIG)
- continue;
+ if (list == 0)
+ {
+ for (i = 0; i <= NSIG; i++)
+ showtrap (i);
+ return (EXECUTION_SUCCESS);
+ }
- t = (p == (char *)IGNORE_SIG) ? (char *)NULL : single_quote (p);
- printf ("trap -- %s %s\n", t ? t : "''", signal_name (i));
- if (t)
- free (t);
+ for (result = EXECUTION_SUCCESS; list; list = list->next)
+ {
+ i = decode_signal (list->word->word);
+ if (i == NO_SIG)
+ {
+ result = EXECUTION_FAILURE;
+ builtin_error ("%s: not a signal specification", list->word->word);
+ }
+ else
+ showtrap (i);
}
- return (EXECUTION_SUCCESS);
+
+ return (result);
}
projects / platform / upstream / bash.git / blobdiff