ex76.sh

Shall高级编程

#!/bin/bash
# Hunting variables with a trap.

trap 'echo Variable Listing --- a = $a  b = $b' EXIT
#  EXIT is the name of the signal generated upon exit from a script.
#
#  The command specified by the "trap" doesn't execute until
#+ the appropriate signal is sent.

echo "This prints before the \"trap\" --"
echo "even though the script sees the \"trap\" first."
echo

a=39

b=36

exit 0
#  Note that commenting out the 'exit' command makes no difference,
#+ since the script exits in any case after running out of commands.