1  import os
       2  
       3  if __name__ == '__main__':
       4      while True:
       5          buf = os.read(0, 1024)
       6          if not buf:
       7              break
       8          try:
       9              os.write(1, b'OUT:'+buf)
      10          except OSError as ex:
      11              os.write(2, b'ERR:' + ex.__class__.__name__.encode('ascii'))