Questions tagged [shell-trap]
18 questions
12
votes
3 answers
Exit after trap fires
Take this script
#!/bin/sh
fd ()
{
echo Hello world
exit
}
trap fd EXIT INT
for g in {1..5}
do
echo foo
sleep 1
done
I would like fd to fire once, either from Control-C or if the script exits normally. However if you hit Control-C it…
Zombo
- 1
- 62
- 391
- 407
8
votes
1 answer
Is trap EXIT required to execute in case of SIGINT or SIGTERM received?
I have a simple script
trap 'echo exit' EXIT
while true; do sleep 1; done
and it behaves differently in different shells:
$ bash tst.sh
^Cexit
$ dash tst.sh
^C
$ zsh tst.sh
^C
$ sh tst.sh
^Cexit
So I'm not sure about how it should operate and…
Ixanezis
- 1,631
- 13
- 20
8
votes
1 answer
Simultaneously watch for signals and process exit in Bourne shell
I have a Bourne shell (/bin/sh) script (for portability) that wants to monitor another program. It should start the other program, then wait for it to exit. When the second program exits, it does some final work and exits itself. The catch is…
Alan De Smet
- 1,699
- 1
- 16
- 20
4
votes
2 answers
Restore traps without a temp file
Without arguments trap prints the currently set commands for all traps. However, a subshell does not inherit traps, so the canonical example for saving and restoring traps fails in bash:
save_traps=$(trap)
...
eval "$save_traps"
The trap on the…
William Pursell
- 204,365
- 48
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4
votes
1 answer
why is this simple bash trap failing
I'm still pretty new to bash scripting, and I'm having a hard time figuring out why this simple trap is not working as expected.
Goal - create an optional waiting period that can be skipped by pressing CTRL+C.
Expected result of pressing CTRL+C -…
Craig Cummings
- 43
- 1
- 3
3
votes
3 answers
trapping shell exit code
I am working on a shell script, and want to handle various exit codes that I might come across. To try things out, I am using this script:
#!/bin/sh
echo "Starting"
trap "echo \"first one\"; echo \"second one\"; " 1
exit 1;
I suppose I am missing…
jpou
- 1,935
- 2
- 21
- 30
2
votes
3 answers
Multiple actions in trap in ksh
After sudo su -, I want to have both the username and timestamp in the k-shell history list. I have the command line:
trap 'who am i|cut -d" " -f1 |tr "\n" " " && date|read -s' debug
With this command, I expect something like:
UserName Tue Oct 13…
Heinz
- 913
- 4
- 12
- 22
1
vote
2 answers
Idiomatic way to exit ksh while loop
I've the following 5 second timer which prints an asterisk for each second.
timer () {
i=1
trap 'i=5' INT
while [[ $i -le 5 ]]; do
sleep 1
printf "*"
((i+=1))
done
}
Somehow the trap chunk seems a little hackish and I wonder if…
amorphousone
- 65
- 1
- 4
1
vote
1 answer
Ending Timestamp not printing on Shell Script: Using trap
I have a shell script I use for deployments. Since I want to capture the output of the entire process, I've wrapped it in a subshell and tail that out:
#! /usr/bin/env ksh
#…
David W.
- 105,218
- 39
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- 337
1
vote
2 answers
custom trap signal in ksh
Is there a way for me to implement custom fake signals in ksh? Currently am capturing the ERR signal and exiting. However, due to a change, there are calls that may not return success, however that is a valid condition. In such case, I want to make…
Kiran
- 993
- 2
- 9
- 14
1
vote
1 answer
Why doesn't script call the cleanup and kill the script after 5s, and I also want to get where it stoppped
The script is designed to kill itself after 5s. But it doesn't kill the script after 5s, and does not call the cleanup.
The important thing is that I want to get the value of i when it stopped.
#!/bin/sh
trap "cleanup" TERM
#call the cleanup when…
user1334609
- 381
- 4
- 12
1
vote
1 answer
Trap syntax issue in bash
I intend to use trap to execute some clean up code in case of a failure. I have the following code, but it seems to be have some syntactical issues.
#!/bin/bash
set -e
function handle_error {
umount /mnt/chroot
losetup -d $LOOP_DEV1…
The Governor
- 1,152
- 1
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0
votes
1 answer
In bash: processing every command line without using the debug trap?
I have a complicated mechanism built into my bash environment that requires the execution of a couple scripts when the prompt is generated, but also when the user hits enter to begin processing a command. I'll give an oversimplified description:
The…
Sniggerfardimungus
- 11,583
- 10
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- 97
0
votes
2 answers
How do I trap EXIT in a solaris 11 shell script?
man signal.h indicates there's no SIGEXIT in Solaris 11. How can I trap it in my shell scripts? Or how can I simulate the old behavior of traping SIGEXT?
user2730089
- 11
- 1
0
votes
2 answers
shell script process termination issue
/bin/sh -version
GNU sh, version 1.14.7(1)
exitfn () {
# Resore signal handling for SIGINT
echo "exiting with trap" >> /tmp/logfile
rm -f /var/run/lockfile.pid # Growl at user,
exit # then exit…
Jatin Bodarya
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