open O, '>', 'foo';
print O "bar\n";
close O;
open O, '>', 'bar';
print O "$_\n" for qw(foo quux wrdlbrmfd);
close O;

open I, '<', 'foo';
while (<I>) {
    chop;
    open II, '<', $_ if -f $_;
    while (<II>) {
        print;
    }
    print "\$_ = '$_'\n";
}
__END__
foo
quux
wrdlbrmfd
$_ = ''