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Top Forums UNIX for Dummies Questions & Answers multiple variables assignement (stdout/stderr outputs) Post 302447903 by anthalamus on Tuesday 24th of August 2010 03:59:37 PM
Old 08-24-2010
multiple variables assignement (stdout/stderr outputs)

Hi all,

I've been looking around for this for a while and can't seem to find a satifactory way to do what I want:

I would like to assign the output of stdout to a variable and that of stderr to another one, and this without using temporary files/named pipes. In other words be able to assign several variable at a time.

For instance:
Code:
touch a_file
STDOUT=$(ls not_a_file a_file) # but error message is lost unless redirected somewhere
ls: cannot access not_a_file: No such file or directory
echo $STDOUT
a_file

Is it even possible? problems with backticks (``) or $(...) is that it only assigns 1 variable at a time I believe. Anyone's got any idea?

I could do:

Code:
STDOUT=$(ls not_a_file a_file 2>&1)
echo $STDOUT
ls: cannot access not_a_file: No such file or directory a_file

and parse the output but is the order even guaranteed? even if it is, distinguishing the stderr part from the stdout one would be difficult...

Thanks!
Anthony

Last edited by anthalamus; 08-24-2010 at 05:53 PM..
 

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Appender::Screen(3pm)					User Contributed Perl Documentation				     Appender::Screen(3pm)

NAME
Log::Log4perl::Appender::Screen - Log to STDOUT/STDERR SYNOPSIS
use Log::Log4perl::Appender::Screen; my $app = Log::Log4perl::Appender::Screen->new( stderr => 0, utf8 => 1, ); $file->log(message => "Log me "); DESCRIPTION
This is a simple appender for writing to STDOUT or STDERR. The constructor "new()" take an optional parameter "stderr", if set to a true value, the appender will log to STDERR. The default setting for "stderr" is 1, so messages will be logged to STDERR by default. If "stderr" is set to a false value, it will log to STDOUT (or, more accurately, whichever file handle is selected via "select()", STDOUT by default). Design and implementation of this module has been greatly inspired by Dave Rolsky's "Log::Dispatch" appender framework. To enable printing wide utf8 characters, set the utf8 option to a true value: my $app = Log::Log4perl::Appender::Screen->new( stderr => 1, utf8 => 1, ); This will issue the necessary binmode command to the selected output channel (stderr/stdout). COPYRIGHT AND LICENSE
Copyright 2002-2009 by Mike Schilli <m@perlmeister.com> and Kevin Goess <cpan@goess.org>. This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.10.1 2010-07-21 Appender::Screen(3pm)
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