The way I restructured the code it is impossible to distinguish a timeout error from other errors; you simply get the "no data available" error from the socket operation. This is the same error you'd get in non-blocking mode.
To distinguish a timeout error, the caller can check s->sock_timeout when a non-blocking mode error occured, or just return an error code from internal_select() (I guess you must have your reason to taken it out in the first place)
I don't understand your first suggestion. Not all errors mean that the timeout triggered!
I took it out because it is much less code this way.
Before I recomplicate the code so that it can raise a separate error when the select fails, I'd like to understand the use case better. Why would you want to make this distinction? Requeueing the request (as in Skip's example) doesn't make sense IMO: you set the timeout for a reason, and that reason is that you want to give up if it takes too long. If you really intend to retry you're better of disabling the timeout!
How about the following (assume we have socket.setDefaultTimeout()):
import socket import urllib socket.setDefaultTimeout(5.0) retry = 0 url = 'some url' while retry < 3: try: file = urllib.urlretrieve(url) except socket.TimeoutError: if retry == 2: print "Server too busy, given up!" raise else: print "Server busy, retry!" retry += 1 else: break
MS IIS behave strangely to http request. When the server is very busy, it will randomly drop some requests without disconnecting the client. So the best approach for the client is to timeout and retry. I guess that might be the reason why people needed timeoutsocket in the first place.
One of the reasons (there are lots of reasons why a connect or receive attempt may be very slow to time out, or even never time out).
Of course, this stll doesn't distinguish between a timeout from connect() and one from recv().
Have you ever written code like this?
If you really want to, you can already distinguish the timeout case, because you get an EAGAIN error then (maybe something else on Windows -- Bernard, if you have a fix for that, please send it to me).
I am struggling with the test case for the new socket code. The timeout test case I've send you works with the old socketmodule.c (attached), but not with the lastest version (on linux or windows). It's strange, your new implementation looks much cleaner.
No need to attach copies of old versions -- just give me the CVS revision number. :-)
Please bear with me a bit longer for a patch :.(
Anyway, I have no time to play with this right now, so I'm glad you aren't giving up just yet. :-)
--Guido van Rossum (home page: http://www.python.org/%7Eguido/)