Remove multiple entries of the same command in .bash_history with preserving the chronological order

cp -a ~/.bash_history ~/.bash_history.bak && perl -ne 'print unless $seen{$_}++' ~/.bash_history.bak >~/.bash_history
Only the first appearance of a repeated command in the history will be kept. Otherwise, if you prefer to keep last occurrence of a repeated command then maybe you can achieve that by including reverse input/output i.e with 'tac' command in expression above. To see statistics of removed repeated commands: diff --suppress-common-lines -y ~/.bash_history.bak ~/.bash_history|uniq -c|sort -n|tr -s " "|sed '/^ 1/d'|grep '<'

By: knoppix5
2019-04-15 12:39:09

What Others Think

Very organized
geebranz · 22 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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