The Bash shell provides command-line tools for editing and manipulating a user's command history. This is primarily a convenience, a means of saving keystrokes.
Bash history commands:
history
fc
bash$ history 1 mount /mnt/cdrom 2 cd /mnt/cdrom 3 ls ... |
Internal variables associated with Bash history commands:
$HISTCMD
$HISTCONTROL
$HISTIGNORE
$HISTFILE
$HISTFILESIZE
$HISTSIZE
$HISTTIMEFORMAT (Bash, ver. 3.0 or later)
!!
!$
!#
!N
!-N
!STRING
!?STRING?
^STRING^string^
Unfortunately, the Bash history tools find no use in scripting.
#!/bin/bash # history.sh # A (vain) attempt to use the 'history' command in a script. history # No output. var=$(history); echo "$var" # $var is empty. # History commands are, by default, disabled within a script. # However, as dhw points out, #+ set -o history #+ enables the history mechanism. set -o history var=$(history); echo "$var" # 1 var=$(history) |
bash$ ./history.sh (no output) |
The Advancing in the Bash Shell site gives a good introduction to the use of history commands in Bash.