Controlling the History and Setting the Shell Editor

Controlling the history

We can control which commands get stored in the history and how many entries are preserved in the current session and across all sessions, all through a handful of shell variables. Let’s add some to our .bashrc file.

The HISTCONTROL variable lets us ignore commands that start with a space. This can be really useful to hide commands containing sensitive information from our history. It’s often a default setting.

The HISTCONTROL variable also lets us ignore repeated duplicates. So, if we type ls three times in a row, we can have it saved only once. This only checks the previous command for duplicates, but it’s still a nice way to trim down the history a bit.

We can set one or both of these options like this:

HISTCONTROL=ignorespace:ignoredups

Better yet, ...