Re: Evaluate expression every time directory changes

[Bob Proulx]

bash_user wrote:
> That is correct.  
> I would like to understand what triggers the shell to re-evaluate
> PROMPT_COMMAND every time 
> directory / clock change occur. 

The documentation for bash says:

       PROMPT_COMMAND
              If set, the value is executed as a command prior to issuing each
              primary prompt.

It is not triggered when the current working directory changes.  It is
triggered every time a prompt is printed.  This is such a small amount
of cpu time that it is probably not worth the effort to make it only
happen when the directory changes.

Bob