In the open doc there is an example: 

close STDOUT;
open STDOUT, '>', \$variable or die "Can't open STDOUT: $!";

[download]

You could combine that with local *STDOUT to limit that capturing to a scope: 

#!/usr/bin/perl
use warnings;
use strict;

sub writes_to_stdout {
        print "some information\n";
}

sub captured {
        local *STDOUT;
        my $result;
        open STDOUT, '>', \$result;
        writes_to_stdout();
        return $result;
}

my $val = captured();
print "No output yet\n";

print "But now: $val";

## and this is what it writes:
$ perl foo.pl
No output yet
But now: some information

[download]

Update: added complete example

Perl 6 in German

In reply to Re: n a perl sub, how do I capture STDOUT, STDERR that comes from another perl sub? by moritz
in thread In a perl sub, how do I capture STDOUT, STDERR that comes from another perl sub? by seank

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