Based on various suggestion received here, here is the tested code. 
use strict;
use warnings;

my $outfile = "test.txt";
open (my $ofh, ">$outfile") or die;

foo ($ofh); #Prints to the file pointed by $ofh

foo(); #Prints to STDOUT

sub foo
{
    my $filehandle= shift;
    $filehandle ||= \*STDOUT ;
    select($filehandle);

    print  <<"EOF";
This is a test, it is only a test. 
In the event of an emergency, run around in a panic.
EOF

}

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artist

In reply to Re: Passing filehandles to subroutines by artist
in thread Passing filehandles to subroutines by ibanix

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