for (glob "*.txt") {
      my $lsoutput = qx(ls -l $_);
      if ($lsoutput =~ /$ENV{USER}/) {
          print "File matches current username.\n";
      }
  }

##</code><code>##

  for (glob "*.txt") {
      open my $lsfh, "-|", 'ls', '-l', $_
          or die "Cannot open 'ls': $!\n";

      while (<$lsfh>) {
          if ($lsoutput =~ /$ENV{USER}/) {
              print "File matches current username.\n";
          }
      }
  }