Python os.pipe() 方法

#!/usr/bin/python

import os, sys

print "The child will write text to a pipe and "
print "the parent will read the text written by child..."

# file descriptors r, w for reading and writing
r, w = os.pipe()

processid = os.fork()
if processid:
   # This is the parent process
   # Closes file descriptor w
   os.close(w)
   r = os.fdopen(r)
   print "Parent reading"
   str = r.read()
   print "text =", str   
   sys.exit(0)
else:
   # This is the child process
   os.close(r)
   w = os.fdopen(w, 'w')
   print "Child writing"
   w.write("Text written by child...")
   w.close()
   print "Child closing"
   sys.exit(0)