From owner-freebsd-questions  Sat Jul 18 04:49:51 1998
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Date: Sat, 18 Jul 1998 13:49:05 +0200
From: Johann Visagie <wjv@cityip.co.za>
To: Greg Lehey <grog@lemis.com>, FreeBSD Questions <questions@FreeBSD.ORG>
Subject: Re: Unsetting exported environment variables?
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On Sat, 18 Jul 1998 at 15:54 SAT, Greg Lehey wrote:
>
> If you try to run SuperProbe with the variable DISPLAY set, it will
> refuse to run.  That's OK with the C shell, you just enter:
> 
> % unsetenv DISPLAY
> % /usr/X11R6/bin/SuperProbe
> 
> Unfortunately, to my knowledge there's no similar function in the
> Bourne shell.  You can set the variable to the null string:

In GNU bash, the shell builtin "export" has a flag "-n", which allows you to
remove the export property from a particular variable.  This does not, to the
best of my knowledge, apply to the standard Bourne shell.

Hmmm, I've just had a look at the man page for sh(1), and found the
following:

     unset name ...
                  The specified variables and functions are unset and
		  unexported.

I've just tested it, and it seems to behave similarly to the C shell's
unsetenv.

-- V

Johann Visagie | Email: wjv@CityIP.co.za | Tel: +27 21 419-7878

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