If you want to add this settings to globally use /etc/bash.bashrc
First you need to Edit your $HOME/.bashrc file
gedit $HOME/.bashrc
Add the following line
export HISTTIMEFORMAT=
"%h/%d - %H:%M:%S "
Save and exit the file.
From next login instead of:
574 tail -f /var/log/maillog
575 mailq | tail -15
576 tail -f /var/log/maillog
577 less /var/log/maillog
you get:
1002 May/09 - 11:46:16 grep log /var/log/maillog
1003 Apr/09 - 14:17:40 passwd test
1004 Apr/09 - 14:50:28 history 15
Some more bash history tips
- The most efficent way to search your history is to hit Ctrl R and type the start of the command. It will autocomplete as soon as there’s a match to a history entry, then you just hit enter
- If you don’t want to save duplicate commands use the following option in your bashrc file ($HOME/.bashrc)
export HISTCONTROL=ignoreboth
- If you want to set the size of the history file use the following option in your bashrc file ($HOME/.bashrc)
export HISTSIZE=500





Really useful tips, thanks.
You forgot to add the history command. it displays the last 500 (or what you have set) commands typed.
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Didn’t work for me (ubuntu 8.04), got this when I logged in again:
-bash: export: `-’: not a valid identifier
-bash: export: `%H:%M:%S’: not a valid identifier
-bash: export: `“’: not a valid identifier
Also I used “export” before all those commands, ie I’m pretty sure “HISTSIZE=500″ should be “export HISTSIZE=500″.
I like your blog. Enjoy getting a new ubuntu thing every couple of days… Thanks.
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@Andre
I have updated article with export command
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Any idea why I’m getting those ‘not a valid identifier’ errors?
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Oh, I’ve fixed it. You should change it to single quotes:
export HISTTIMEFORMAT=’%h/%d - %H:%M:%S ‘
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thanks for the tip
love this site
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Any idea how to setup a new user so that hitting tab will complete a word, up will show the last history, and on top of that the prompt will say user@machine: rather than just $:
The initial user you create during setup has these settings but new ones do not and it drives me crazy. I tried copying the whole bashrc over and no luck.
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I fit into the first category. ,
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