cafuego

  if ($_SERVER['argc'] == 1) {
    $file = 'php://stdin';
  }
  else if ($_SERVER['argv'][1] == '-') {
    $file = 'php://stdin';
  }
  else {
    if (file_exists($_SERVER['argv'][1])) {
      $file = $_SERVER['argv'][1];
    }
    else {
      printf("No such file or directory: %s\n" . $_SERVER['argv'][1]);
      exit(1);
    }
  }

  $fp = fopen($file, 'r');
  if (!$fp) {
    printf("Cannot open file for reading: %s\n", $file);
    exit(1);
  }

  while (!feof($fp)) {
    $line = trim(fgets($fp, 1024));
    printf("%s\n", strrev($line));
  }

  fclose($fp);