How to output backtick or qx to a variable and STDOUT at the same time?

dr.jekyllandme has asked for the wisdom of the Perl Monks concerning the following question:

Hello, I have a program that issues some system calls. I would like to do 2 things in my function - The system call's output should be stored in a variable and also output to STDOUT. I guess I am asking for a way to combine both system and qx( backtick ). Is this even possible? Here is a snapshot of my code:

#!usr/bin/perl

use strict;
use warnings;

my $cmd = qx("ls -l");
print "$cmd";
[download]

Thank you.

Comment on How to output backtick or qx to a variable and STDOUT at the same time? Download Code

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Re: How to output backtick or qx to a variable and STDOUT at the same time? by Athanasius (Archbishop) on Nov 20, 2012 at 06:03 UTC
I’m not exactly clear on what you want, but the CPAN module Capture::Tiny will almost certainly meet your needs. For example (from the documentation): `($stdout, $stderr, $exit) = capture { system($cmd, @args); };` [download] Update: For your specific example: `#!usr/bin/perl use strict; use warnings; use Capture::Tiny qw(capture); my ($stdout, $stderr, $exit) = capture { system('ls', '-l'); }; print "After the system call:\n"; print "\$stdout = $stdout\n"; print "\$stderr = $stderr\n"; print "\$exit = $exit\n";` [download] Hope that helps, Athanasius <°(((>< contra mundum	[reply] [d/l] [select]
Re^2: How to output backtick or qx to a variable and STDOUT at the same time? by dr.jekyllandme (Sexton) on Nov 20, 2012 at 06:43 UTC
Thank you! Looking over at Capture::Tiny's doc, I found tee. Which is exactly what I needed. Output both to STDOUT and store in a variable for later use. `#!usr/bin/perl use strict; use warnings; use Capture::Tiny qw(capture tee); my ($stdout, $stderr, $exit) = tee { system('ls', '-l'); }; print $stdout;` [download]	[reply] [d/l]
Re: How to output backtick or qx to a variable and STDOUT at the same time? by Utilitarian (Vicar) on Nov 20, 2012 at 08:39 UTC
What I suspect your tutor wants you to prove you understand is that assignment returns the value assigned on success. Try the following `perl -e 'print $out=qx(ls );print "+" x 80 , "\n";print $out'` [download] `print "Good ",qw(night morning afternoon evening)[(localtime)[2]/6]," fellow monks."`	[reply] [d/l] [select]
Re: How to output backtick or qx to a variable and STDOUT at the same time? by space_monk (Chaplain) on Nov 20, 2012 at 08:36 UTC
As far as combining system and backtick operation is concerned, it seems to be a little known fact that backticks also set the exit code ($?) value in the same way as system does. I'd personally be grateful if someone could show an example of where Capture:Tiny does something that is not done by backticks. A Monk aims to give answers to those who have none, and to learn from those who know more.	[reply]