The  -l command-line parameter will cause the contents of $\, undefined by default, to be assigned  "\n" and also to be appended at the end of print each time it is called (see perlrun): are you using  -l on your command line?

Also, setting  $| to true causes unbuffered output: each print is printed whether or not it has a newline terminator. (Output is buffered by default.) See  $| in perlvar and also Suffering from Buffering.

c:\@Work\Perl>perl -wMstrict -e
"{
 local $| = 1;
 ;;
 for my $n (reverse 1 .. 5, '(unbuffered)') {
   sleep 1;
   print qq{$n };
   }
 }
 ;;
 for my $s ('(buffered)', 'Blast', 'Off', 'Now', qq{\n}) {
   sleep 1;
   print qq{$s };
   }
"
(unbuffered) 5 4 3 2 1 (buffered) Blast Off Now
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