-p      causes Perl to assume the following loop around your
        program, which makes it iterate over filename arguments
        somewhat like sed:

LINE:
while (<>) {
...             # your program goes here
} continue {
    print or die "-p destination: $!\n";
}
[download]

So the next statement makes continue block executed. I think -n with explicit print is the better solution. Or maybe you can try a $_="" (untested, just a thought).