How to avoid duplicate entries in .bash_history
From the bash
man page:
HISTCONTROL
A colon-separated list of values controlling how commands are saved on the history list. If the list of values includes
ignorespace
, lines which begin with a space character are not saved in the history list. A value ofignoredups
causes lines matching the previous history entry to not be saved. A value ofignoreboth
is shorthand forignorespace
andignoredups
. A value oferasedups
causes all previous lines matching the current line to be removed from the history list before that line is saved. Any value not in the above list is ignored. If HISTCONTROL is unset, or does not include a valid value, all lines read by the shell parser are saved on the history list, subject to the value of HISTIGNORE. The second and subsequent lines of a multi-line compound command are not tested, and are added to the history regardless of the value of HISTCONTROL.
So put the following line in your ~/.bashrc
:
export HISTCONTROL=ignoreboth:erasedups
Stick this in your ~/.bashrc
:
export HISTCONTROL=ignoredups
You could instead use ignoreboth
. This it shorthand for both ignorespaces
(commands starting with spaces) and ignoredups
(duplicates).
I prefer ignoredups
on its own as I find the default behaviour of ignoring commands with spaces at the front quite annoying when I copy a command off a website and it doesn't get saved because I accidentally copied in a space too.... But to each their own.
Putting this in ~/.bashrc
will apply @alvin's solution across different sessions as wlell
HISTCONTROL=ignoredups:erasedups
shopt -s histappend
PROMPT_COMMAND="history -n; history -w; history -c; history -r; $PROMPT_COMMAND"
Source: Linux: Bash history: “ignoredups” and “erasedups” setting conflict with common history across sessions