die("\\n ne LF\n")
   if "abc\n" ne "abc\x0A";

print("\\n eq LF\n");

$s = "abc";
$l1 = length($s);
chomp($s);
$l2 = length($s);
if ($l1 - $l2 == 0) {
   print("abc unchanged\n");
} else {
   print("???\n");
}

$s = "abc\n";
$l1 = length($s);
chomp($s);
$l2 = length($s);
if ($l1 - $l2 == 1) {
   print("\\n removed from abc\\n\n");
} elsif ($l1 - $l2 == 0) {
   print("abc\\n unchanged\n");
} else {
   print("???\n");
}

$s = "abc\r\n";
$l1 = length($s);
chomp($s);
$l2 = length($s);
if ($l1 - $l2 == 2) {
   print("\\r\\n removed from abc\\r\\n\n");
} elsif ($l1 - $l2 == 1) {
   print("\\n removed from abc\\r\\n (\\r kept)\n");
} elsif ($l1 - $l2 == 0) {
   print("abc\\r\\n unchanged\n");
} else {
   print("???\n");
}

__END__
ActivePerl v5.8.0 on WinXP
--------------------------
\n eq LF
abc unchanged
\n removed from abc\n
\n removed from abc\r\n (\r kept)