old_contents: #!/usr/bin/python
  
  import subprocess, os, sys
  
  if len(sys.argv) < 2:
      print('Must specify file names of 2 chess engines')
      for i in range(len(sys.argv)):
          print(str(i) + ': ' + sys.argv[i])
      sys.exit(1)
  
  generator = './' + sys.argv[-2]
  checker = './' + sys.argv[-1]
  game_file = 'game.pgn'
  count = 0
  
  while True:
      try:
          os.remove(game_file)
      except OSError:
          pass
  
      count += 1
      print('Game #' + str(count))
  
      out = subprocess.run([generator, '-random', '-random'])
      if not os.path.isfile(game_file):
          print('Game file not produced: ' + game_file)
          print('generator = ' + generator)
          print(out.returncode)
          print(out.stdout)
          print(out.stderr)
          sys.exit()
  
      result = subprocess.run([checker, '-confirm', game_file])
      if result.returncode != 0:
          print('Found discrepancy. See ' + game_file)
          print('generator = ' + generator)
          print('checker = ' + checker)
          sys.exit()
  
      generator, checker = checker, generator
  
new_contents: #!/usr/bin/python
  
  import subprocess, os, sys
  
  if len(sys.argv) < 2:
      print('Must specify file names of 2 chess engines')
      for i in range(len(sys.argv)):
          print(str(i) + ': ' + sys.argv[i])
      sys.exit(1)
  
  generator = './' + sys.argv[-2]
  checker = './' + sys.argv[-1]
  game_file = 'game.pgn'
  count = 0
  
  while True:
      try:
          os.remove(game_file)
      except OSError:
          pass
  
      if os.path.isfile(game_file):
          print('Could not delete output file:', game_file)
  
      count += 1
      print('Game #' + str(count))
  
      out = subprocess.run([generator, '-random', '-random'])
      if not os.path.isfile(game_file):
          print('Game file not produced: ' + game_file)
          print('generator = ' + generator)
          print(out.returncode)
          print(out.stdout)
          print(out.stderr)
          sys.exit()
  
      result = subprocess.run([checker, '-confirm', game_file])
      if result.returncode != 0:
          print('Found discrepancy. See ' + game_file)
          print('generator = ' + generator)
          print('checker = ' + checker)
          sys.exit()
  
      generator, checker = checker, generator
  
subject: Check that engine fight files are deleted before test