如何检测Python中的fifo已被删除

Question

In Python, I can poll for incoming data on a fifo (created with the Linux mkfifo command) with:

reader = open(known_fifo_name,"r")
while True:
   data = reader.read(1)
   if data:
      process(data)
   else:
      time.sleep(0.1) #no data now, try later

But read() returns the empty string both when there is no data, and when the fifo has been deleted (by an external program with a remove() call).
Is there a way to tell that the fifo I am listening to no longer exists?

Answer 1

You can do the following:

import os
try:
    os.stat(reader.fileno())
except OSError:
    # The FIFO has gone away
sleep(0.1)  # Wait for some more input