From: Randall R Schulz <rrschulz@cris.com>
To: Gerald Reno <grenoml@yahoo.com>, cygwin@cygwin.com
Subject: Re: Cygwin 1.3.10 read command and W2K
Date: Fri, 07 Jun 2002 01:09:00 -0000 [thread overview]
Message-ID: <5.1.0.14.2.20020606224316.01bfadc8@pop3.cris.com> (raw)
In-Reply-To: <20020606200157.84987.qmail@web14405.mail.yahoo.com>
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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next prev parent reply other threads:[~2002-06-07 5:52 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-06-06 15:14 Gerald Reno
2002-06-07 1:09 ` Randall R Schulz [this message]
2002-06-07 9:10 ` Gerald Reno
2002-06-06 15:17 Gerald Reno
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