From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Updating the program caller's environment from the called program
Date:	19 Jul 2000 13:25:12 GMT
Organization:	Aachen University of Technology (RWTH)
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To:	djgpp AT delorie DOT com
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west.usenetserver.com <glenm AT myself DOT com> wrote:

> So the problem is currently I have not figured out how to update the
> caller's environment.  

Within the limits of 'documented' DOS services, you can't do that. You
have to do some dirty undocumented tricks to walk the chain of memory
blocks managed by DOS, and find the environment of the calling
program. One big problem with this is that this environment block will
often not have enough 'slack' space to store big changes in,
i.e. you'll likely end up with 'out of environments space' situations.

Your current trick of using a batch file only works if the calling
program is command.com. You can't use the same trick to update another
program's environment.



-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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