Bash script demonstrating how to handle signals and clean up after yourself when the script is ended unexpectedly.

bash-signals.sh

#!/bin/bash

temp_dir="/tmp"
if [ -d "${TEMP}" ]; then
	temp_dir="${TEMP}"
fi
this_file="$(basename ${0})"
temp_file="${temp_dir}/${this_file%.*}.$$.$RANDOM"

function cleanup {
	rm --verbose "${temp_file}"
	exit
}

function handle_hup {
	echo "Hup hup hup!"
	echo "(Received SIGHUP -- Terminal window closed.)"
	cleanup
}

function handle_int {
	echo "Kock kock."
	echo "Who's there?"
	echo "Interupting cow."
	echo "Interupting co--"
	echo "MOO!"
	echo "(Received SIGINT -- ctrl-c)"
	cleanup
}

function handle_term {
	echo "I'll be back."
	echo "(Received SIGTERM -- kill command)"
	cleanup
}

trap handle_hup SIGHUP
trap handle_int SIGINT
trap handle_term SIGTERM

touch ${temp_file}
while true; do
	clear
	echo "The time is $(date)"
	echo "My pid is $$"
	echo "I created a file at ${temp_file}, but I will clean it up when you give the signal."
	sleep 5
done