Hi,
I'm using Ksh on HP 10.2.
My parent shell script has ignored INT signal using trap command.
trap "" 2 3 .... (other signals)
This script calls another script in which INT signal should be active and should not be ignored.
I browsed the net and found out that in ksh, once a... (1 Reply)
hi
OS: Sun Solaris
I have a scenario that when someone presses ctrl-c while executing a shell script, it should not just exit. it should kill all the child processes started by the running shell script only.
I am executing many other scripts parallely which in turn fork off more... (2 Replies)
Is it ok to use exit() inside a signal handler?
I catch SIGUSR1 in a signal handler and I try to close a file and then exit. The result is inconsistent. Sometimes the process exit and sometimes it returns to the original state before the signal handler was invoked.
Perhaps exit is not legal in... (8 Replies)
Hi,
I am using ksh to write my shell script. I need to create multiple-level of nested sub shells in my script. Lets say I have at n th subshell. My question is how do I come out from there to main login shell.
If I use 'exit' command then it is exiting from just one subshell and back to... (4 Replies)
Hi all,
I am using the trap command in my script, and I want it to trap the signal based on the exit code the script returns.
can anybody tell me how can I use "if loop" for "trap" command.
I want to print
"terminated by user" if signal is SIGINT or 2
"failure" if signal is not 2 and not 0... (1 Reply)
Im sure it has something to do with the wait() call, but everything ive tried either leaves me with a zombie or with the exec executing indefinitely.
switch(pid = fork())
{
case -1:perror("fork failed");
exit(1);
case 0:
if(key == "cd")
{
execl("/bin/cd", "cd",... (2 Replies)
I've search the various posts in these forums, but have not come up with a solution to my problem.
I have a parent process that calls a child script, runs it in the background and the parent finishes - without waiting for the child process to complete. Inside the child, a trap is issued to trap... (6 Replies)
hi,
I have a job that spawns multiple child processes in background.. Catch is i want to wait for some jobs to finish before i spawn more background processes. (each job creates a file and deletes at the end of it . so i don't want start new jobs after x amount of disk size is used up)
now,... (2 Replies)
Hi,
I have parent script which is invoking multiple child scripts. I would want to kill all the child processes before the parent
process exit.
> cat ./parent
#!/bin/ksh
while
do
. ./child arg1 &
if ; then
break
fi
done
Is there a way to get the process group id for all the child... (3 Replies)
First time trying to work with signals in Perl.
Reviewing example I try it, but not able to get it work for 'exit'.
I hope, I am correct, assuming, that the ending any code by
exit $return_code;
the $SIG{EXIT} should be de-referenced and processed?!
So, I have such code, that, I assume,... (5 Replies)
Discussion started by: alex_5161
5 Replies
LEARN ABOUT OPENDARWIN
trap
trap(1) User Commands trap(1)NAME
trap, onintr - shell built-in functions to respond to (hardware) signals
SYNOPSIS
sh
trap [ argument n [n2...]]
csh
onintr [-| label]
ksh
*trap [ arg sig [ sig2...]]
DESCRIPTION
sh
The trap command argument is to be read and executed when the shell receives numeric or symbolic signal(s) (n). (Note: argument is scanned
once when the trap is set and once when the trap is taken.) Trap commands are executed in order of signal number or corresponding symbolic
names. Any attempt to set a trap on a signal that was ignored on entry to the current shell is ineffective. An attempt to trap on signal 11
(memory fault) produces an error. If argument is absent all trap(s) n are reset to their original values. If argument is the null string
this signal is ignored by the shell and by the commands it invokes. If n is 0 the command argument is executed on exit from the shell. The
trap command with no arguments prints a list of commands associated with each signal number.
csh
onintr controls the action of the shell on interrupts. With no arguments, onintr restores the default action of the shell on interrupts.
(The shell terminates shell scripts and returns to the terminal command input level). With the - argument, the shell ignores all inter-
rupts. With a label argument, the shell executes a goto label when an interrupt is received or a child process terminates because it was
interrupted.
ksh
trap uses arg as a command to be read and executed when the shell receives signal(s) sig. (Note that arg is scanned once when the trap is
set and once when the trap is taken.) Each sig can be given as a number or as the name of the signal. trap commands are executed in order
of signal number. Any attempt to set a trap on a signal that was ignored on entry to the current shell is ineffective. If arg is omitted
or is -, then the trap(s) for each sig are reset to their original values. If arg is the null (the empty string, e.g., "" ) string then
this signal is ignored by the shell and by the commands it invokes. If sig is ERR then arg will be executed whenever a command has a non-
zero exit status. If sig is DEBUG then arg will be executed after each command. If sig is 0 or EXIT for a trap set outside any function
then the command arg is executed on exit from the shell. The trap command with no arguments prints a list of commands associated with each
signal number.
On this man page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a vari-
able assignment. This means that tilde substitution is performed after the = sign and word splitting and file name generation are not
performed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO csh(1), exit(1), ksh(1), sh(1), attributes(5)SunOS 5.10 23 Oct 1994 trap(1)