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Date: Fri, 27 Oct 2006 06:03:37 -0600
From: Eric Blake <ebb9 AT byu DOT net>
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To: cygwin AT cygwin DOT com
Subject: Re: Piping to the 'read' command
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According to Jim Easton on 10/27/2006 1:43 AM:
> Hi,
> 
> Fri, 27 Oct 2006 Ian Taylor wrote:
>> Can anyone explain what is happening here (using pdksh as my shell) when
>> I try to set an environment variable using 'read':

This is one of the bash FAQs.  Read E4 on
http://cnswww.cns.cwru.edu/~chet/bash/FAQ

> 
> This suggests to me that it is executing that read in a subshell that
> can't pass the variable back to its parent.  This dispite the fact that
> it appears to be the same process.  (see inserted echo $$)

Sorry, but POSIX requires $$ to be the same in subshells as it is in the
parent, even though that means that in subshells, it is not the parent
process id, but the grandparent.  There is no way, using $$, to tell
subshells apart from the original.

- --
Life is short - so eat dessert first!

Eric Blake             ebb9 AT byu DOT net
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