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Date:	Thu, 06 Jun 2002 22:53:29 -0700
To:	Gerald Reno <grenoml AT yahoo DOT com>, cygwin AT cygwin DOT com
From:	Randall R Schulz <rrschulz AT cris DOT com>
Subject:	Re: Cygwin 1.3.10 read command and W2K
In-Reply-To:	<20020606200157.84987.qmail@web14405.mail.yahoo.com>
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Gerald,

[ The usual disclaimer: None of this is Cygwin specific. ]


When you use a pipe, the shell forks. In your example, the read command was 
occurring in a forked sub-shell, and hence the side-effect on $var is not 
seen in the shell that reads and interprets the pipeline you gave (and 
subsequent commands).

Compare the output of this pipeline:

% echo foo |read bar; echo $bar

%

With that of this one:

% echo foo | (read bar; echo $bar)
foo
%


Depending on the complexity of your script, this construct might work:

% bar="$(echo foo)"
% echo $bar
foo


Randall Schulz
Mountain View, CA USA



At 13:01 2002-06-06, Gerald Reno wrote:
>I have scripts with reads that are failing.  Why doesn't "echo text | read 
>var; echo $var" work?  var is just empty.  Doesn't 'read' default to 
>stdin?  All other commands seem to be working only read is having problem.


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