Hi,
I use non-blocking io to check for timeouts. Sometimes I get EAGAIN (Resource
temporarily unavailable)
on write(). My working code looks like this. But I am unsure how many bytes
have been written to the
pipe if I get an EAGAIN IOError. Up to now I retry with the same chunk.
If I get EAGAIN can I just sleep, and then retry with the same data chunk?
pipe=subprocess.Popen(cmd, stdin=subprocess.PIPE, bufsize=-1)
fcntl.fcntl(pipe.stdin, fcntl.F_SETFL, os.O_NONBLOCK)
....
chunk_size=1024
while select.select([], [pipe.stdin], [], 5):
check_timeout()
chunk=fd.read(chunk_size)
for i_eagain in range(10):
try:
pipe.stdin.write(chunk)
except IOError, exc:
if exc.errno==errno.EAGAIN:
logging.info('write to pipe %s EAGAIN. I will try again
i=%s. %s' % (cmd, i_eagain, exc))
time.sleep(.3)
continue
logging.error('write to pipe %s failed: %s' % (cmd, exc),
exc_info=True)
raise
break # write was successful (default)
else:
raise Exception('Too many EAGAIN on write %s %s' % (cmd, exc),
exc_info=True)
Thomas
--
Thomas Guettler, http://www.thomas-guettler.de/
E-Mail: guettli (*) thomas-guettler + de
--
http://mail.python.org/mailman/listinfo/python-list
