use Benchmark;

timethese(1, {
  'Trial1 While' => sub {
      open (FILE, "file2") or die "Can't open file:  $!\n";
      while (<FILE>) {
          last; # read one line and exit
      }
      close FILE;
  },
  'Trial2 Foreach' => sub {
      open (FILE, "file1") or die "Can't open file:  $!\n";
      foreach my $line (<FILE>) {
          last; # read one line and exit
      }
      close FILE;
  },
});