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From: jik@athena.mit.edu (Jonathan I. Kamens)
Newsgroups: comp.unix.shell
Subject: Re: /bin/sh: How to retain variables set in a while loop?
Keywords: sh, while loop, variables
Message-ID: <1991Mar7.022149.29423@athena.mit.edu>
Date: 7 Mar 91 02:21:49 GMT
References: <1991Mar5.025314.2317@lingua.cltr.uq.OZ.AU> <9209@exodus.Eng.Sun.COM>
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Organization: Massachusetts Institute of Technology
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In article <9209@exodus.Eng.Sun.COM>, mcgrew@ichthous.Eng.Sun.COM (Darin McGrew) writes:
|> If the while loop has its stdio redirected in any way, it is put
|> in a subshell.  (Likewise with for loops, case statements, etc.)
|> The subshell has no way to pass variables back to its parent
|> shell.

  I just want to point out that this problem is eliminated in some newer
versions of the bourne shell, and also in some other shells (including, I
believe, bash and ksh) that use the bourne shell's language.

  Of course, the C shell gets around the problem by not allowing redirection
into loops at all :-).

-- 
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