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

main(@ARGV);

sub main {
    my ($file1, $file2) = @_;
    open my $fh, '<', $file1 or die $!;
    print "first: $_" while <$fh>;
    close $fh;

    again($fh, $file2);
    print "again: $_" while <$fh>;
}

sub again {
    my ($fh, $name) = @_;
    open $fh, '<', $name or die $!;
}