Linux/Unix history with date and time

It is useful to run history command with date and time along with each command. Here are instructions on how to do it on Linux/Unix.

Using environment variable $HISTTIMEFORMAT

Here we are setting HISTTIMEFORMAT on command line.

$ HISTTIMEFORMAT="%c " history
  ...
  ...
  495  Fri 25 Mar 2016 08:04:32 PM UTC pwd
  496  Fri 25 Mar 2016 08:04:32 PM UTC ls
  501  Fri 25 Mar 2016 08:11:01 PM UTC HISTTIMEFORMAT="%c " history

As per strftime manual:

%c: The preferred date and time representation for the current locale

Setting $HISTTIMEFORMAT in .bash_profile

Add the following line to ~/.bash_profile

export HISTTIMEFORMAT="%c "

And source the .bash_profile to load it in current shell (next login it would not be needed).

$ source ~/.bash_profile

Now running the history command will show date and time also