Setting environment from inside a pg.

[Jonathan R. Herr]

gangwani at andromeda.rutgers.edu.rutgers.edu (Sunil Gangwani) writes:

> 
> Hi,
> 
> With the system() function call a new shell is executed in
> DOS or UNIX.  I would like the set an environment variable from
> inside a program so that the variable exists when I exit the
> program??
> 
> Ex. in DOS
> 
> system("set var=Hello");
>
> The above will not work because a new command.com is executed
> and exited immediately.  How can I overcome this simple problem??

Well, you don't say what C you're using.  But, there is a way to set
environment variables in Turbo C 2.0 by use of the putenv(const char *name)
command.  It is also availble on Unix systems according to the
reference guide.  Something like this might work:

/* ========================================== */

#include <stdlib.h>

putenv("set var=Hello");

/* ========================================== */

My syntax may be off base.  I'm not super-experienced in C like some
of these folk.  I only know this much as I've been using getenv() to access
some environment variables for a program I've been writing for Waffle
BBS in which I have to locate a definition file that is defined as an
environment variable and I saw the reference to putenv().

> Please respond directly to gangwani at andromeda.rutgers.edu because
> due to heavy traffic our facility removes USENET stuff every two
> days...

I'll forward it to you.

> Sunil Gangwani

Jon Herr



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|Jonathan R. Herr (aka Jon)	|  herrj at silver.ucs.indiana.edu |
|                               |  herrj at valnet.UUCP            |
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