History substitution fails when implemented in shell script

Question

The below command works in command line

rsync -avh -r /Source/09_03_2016/ /Destination/
echo $(basename !:3)

Output 09_03_2016

But when I do this in shell script it does not work

#! /bin/bash

/usr/bin/rsync -avh -r /Source/09_03_2016 /Destination/;
echo $(basename !:3)

Output !:3

Are u sure u are using bash shell? type command ps $$ tell output.. — TKHN, Oct 07 '16 at 09:34
Why did you add a `;` at the end of the `rsync` command line in the script? — Kusalananda, Oct 07 '16 at 09:46
@GC13 It's a history expansion construct, which is meant for interactive use and not really useful in a script. — Gilles 'SO- stop being evil', Oct 09 '16 at 23:58
Just write `/Source/09_03_2016`! History expansion is meant for typing things quickly. It has no business obfuscating a script. — Gilles 'SO- stop being evil', Oct 09 '16 at 23:59

score 5 · Accepted Answer · answered Oct 07 '16 at 10:05

Use the following directives in your script:

set -o history
set -o histexpand

This will enable the history expansion which is only enabled for interactive shells by default.

See man bash section HISTORY EXPANSION and SHELL BUILTIN COMMANDS command set for details.

1 Answers1