What signal is sent when you close a bash terminal to the programs it was running

Here's a script that generates a script that will try to catch all signals. The script it generates (sigcatcher.sh) outputs the name of the caught signal before exiting.

#!/bin/sh # generate a shell function for each and every available signal. /bin/kill -l | tr ' ' '\n' | while read signal; do cat <<END_OF_FUNCTION handle_$signal () { echo "Caught $signal" exit } trap 'handle_$signal' $signal END_OF_FUNCTION done >sigcatcher.sh echo 'echo "$$"; sleep 600' >>sigcatcher.sh 

On my system (OpenBSD), /bin/kill -l generates a list of available signals on one line, that's why the tr is there to break it up.

The generated script will look something like this:

handle_HUP () { echo "Caught HUP" exit } trap 'handle_HUP' HUP handle_INT () { echo "Caught INT" exit } trap 'handle_INT' INT 

(etc.)

And it will be finished off with

echo "$$"; sleep 600 

It outputs its PID and sleeps for 10 minutes.

You run it like this:

$ sh ./sigcatcher.sh >sigcatcher.out 

Then you close the window, and then you inspect sigcatcher.out.

I don't run X Windows, but when I kill the tmux pane that this script is running in, I get "Caught HUP" in the output file.