[Nottingham] Bash Variables

[Dan Mackdermott]

Hi Mike,

Mike Haber wrote:
> When using bash and exporting variables, is there a way of listing the
> previous values that a variable contained?

The safest thing to do is to save a copy of the variable before it gets 
changed.

> For example if a script is run that contains 'export foo=bar' can the
> previous values for $foo be accessed after the script has run?

After the execution of the script, the shell that the script was running 
under terminates and any variables are unset.

However if you want to gain access to variables from the parent process 
whilst the script is running, you could do some jiggery pokery with the 
$PPID which is the parent process id and 'ps -exwww' which will report 
environment variables from different processes.

I know it's not a complete solution but it's a start...

Cheers,

Dan

-- 
Dan Mackdermott RHCE (Director)
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