You can localize STDOUT and STDERR this way: 
sub printInformationWrapper {
    open (local *STDOUT,'>',\(my $var));
    thing that prints to STDOUT
    return $var;
}

[download]
This method sometimes has problems with printing Unicode. (unless you use open ':utf8'; use encoding 'utf8';, which is the right way to go for unicode anyway).

This is supposed to work without the pragmata (http://community.livejournal.com/ru_perl/183306.html): 

{
    open (local *STDOUT,'>:utf8',\(my $b="\x{FEFF}"));
    printing_stuff
        return $b;
}

[download]
though I've not tested it.

IO::String is probably a less magical way to tie a filehandle to a string. Then you localize STDOUT like above, assigning your filehandle.

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

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