Unable to echo last executed within .sh script

Question

Using following on

cmd=$(uname -a)

printf "["!:0"]"

gives me

[cmd1=Linux localhost.localdomain 2.6.32-300.10.1.el5uek #1 SMP Wed Feb 22 17:37:40 EST 2012 x86_64 x86_64 x86_64 GNU/Linux]

but when is done in test.sh

#!/bin/bash
output=$(uname -a)


printf "["!:0"]"

I'm getting

[!:0]

Thanks.

Answer 1

If you need to get the previous command executed inside a bash (v4+) script,

#!/bin/bash -i
# -i: interactive mode, enable history inside script
set -o history  # enable history, for old bash versions

cmd=$(uname -a)
history | sed -n 'x;${s/ *[0-9]\+ *\(\S*\)/\1/p}'  # print the line before last history entry after removing index