Path: utzoo!attcan!uunet!lll-winken!ames!ncar!boulder!sunybcs!rutgers!cmcl2!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn )
Newsgroups: comp.unix.wizards
Subject: Re: Set parent env with csh script
Message-ID: <9314@smoke.BRL.MIL>
Date: 8 Jan 89 04:58:00 GMT
References: <174@v7fs1.UUCP>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 20

In article <174@v7fs1.UUCP> mvp@v7fs1.UUCP (Mike Van Pelt) writes:
>I would like to write a shell script (csh preferred) that will
>set a few environment variables to various things.  Of course,
>just doing   setenv foo bar  in the script only works for that
>subshell and its children, not for the calling shell.  I've
>gone back and forth through all the likely places in the manuals,
>and haven't found any mention of this.

It's implicit in the description of how environment variables work.

>Is it possible for a subshell to changes the calling shell's 
>environment?  How?

There is no official way for a subprocess to alter an ancestor
process's environment.  Specialized ways can be devised.  In
your case, however, probably all you need is to realize that
SOURCING a shell script (as opposed to EXECUTING it) causes the
changes to occur in the invoking shell context (as opposed to
a subprocess context).  Thus you can alter environment variable
via a sourced script that does setenv (or Bourne shell equivalent).