Does bash have a hook that is run before executing a command?

Posted by Gilles on Super User See other posts from Super User or by Gilles
Published on 2010-08-14T11:09:20Z Indexed on 2012/03/22 11:33 UTC
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bash

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hook

In bash, can I arrange for a function to be executed just before running a command?

There is $PROMPT_COMMAND, which is executed before showing a prompt, i.e., just after running a command.

Bash's $PROMPT_COMMAND is analogous to zsh's precmd function; so what I'm looking for is a bash equivalent to zsh's preexec.

Example applications: set your terminal title to the command being executed; automatically add time before every command.

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