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Mail Archives: djgpp/1997/06/25/12:04:06

Message-Id: <1.5.4.32.19970625160147.00679f4c@dce03.ipt.br>
Mime-Version: 1.0
Date: Wed, 25 Jun 1997 13:01:47 -0300
To: fighteer AT cs DOT com, djgpp AT delorie DOT com
From: Cesar Scarpini Rabak <csrabak AT dce03 DOT ipt DOT br>
Subject: Re: How to read/modify environment variables?

At 19:44 24/06/97 +0000, John M. Aldrich wrote:
>Martin Bernreuther wrote:
>> 
>> I like to write a small tool to add a path to the PATH variable
>> only if it's not already in.
>> How can I get a hold of the environment variables?
>> Is there already a tool to do this?
>> Is there maybe a tool just to search a environment variable for
>> a string?
>
>getenv().  Look it up in the libc docs.  See also its complement,
>putenv().

Humm...John, I'm affraid that won't cut in the Martin's desires!

Putenv will only change the environment of the program and its children but
not the main environment, so is if you add a path to the path variable,
after your program return you loose your modification.

AFAIK, messing _permanently_ in the environment requres hacking into DOS.
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Cesar Scarpini Rabak                      E-mail: csrabak AT ipt DOT br
DME/ASC                                   Phone: 55-11-268-3522 Ext.350
IPT - Instituto de Pesquisas Tecnologicas Fax:   55-11-268-5996
Av. Prof. Almeida Prado, 532.  Sao Paulo - SP 05508-901 BRAZIL
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