named pipe question

[Rajarshi Guha]

Hi,
  I'm having a little trouble when I read from a named pipe. I create a
pipe by

os.mkfifo('/tmp/mypipe')

and then open it for reading with

fin = open('/tmp/mypipe','r+')

(I don't use 'r' as that cause the open command to block). However when I
do from another terminal:

ls -l /tmp/mypipe

and then from my Python session do:

fin.readlines()

it just hangs and I have to Ctrl-C to get out. But when I do from a
terminal:

ls -l /tmp/mypipe ; cat < /tm/mypipe 

I get the output of the ls command. Why does'nt Python read from the pipe
when some other program writes to it?

Thanks,
Rajarshi