To: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: environment and system calls
From: alane AT wozzle DOT linet DOT org (J. Alan Eldridge)
Date: Sat, 02 Jan 93 09:09:07 EST
Organization: Disorganization

Eric Backus <src4src!mcdhup!rutgers!lsid.hp.com!ericb> writes:

> > >I want to communicate with a subprocess that I spawn using the system 
> > >command.  I tried to do this by setting some environment variables
> > >using setenv().
> > 
> > The child runs off go32's environment, unfortunately.
> 
> It seems like we could make a new "turbo-assist" entry for setenv(),
> to set go32's environment and thus the child's environment.  Would
> this leave the parent's environment modifies when go32 exits?  If so,
> we'd have to work around that somehow.

Yes, we could do that... _but_ there's no spare environment space to
modify (thank you MSDOS). When DOS spawns a child process, and in this
case go32 is a child of the command processor, it only allocates as
many bytes as are used in the parent's environment, not the number 
specified for the master environment in config.sys. This is a defect in
DOS, and I'm not sure of a good workaround.

alane AT wozzle DOT linet DOT org (J. Alan Eldridge)
Fido: The University of Walamaloo 1:272/38.473