New submission from Trent Nelson <[EMAIL PROTECTED]>: Background: I came across this issue when trying to track down why test_asynchat would periodically wedge python processes on the Windows buildbots, to the point that they wouldn't even respond to SIGKILL (or ctrl-c on the console).
What I found after a bit of digging is that Windows doesn't raise EADDRINUSE socket.errors when you bind() two sockets to identical host/ports *IFF* SO_REUSEADDR has been set as a socket option. Decided to brighten up my tube journey into work this morning by reading the Gospel's take on the situation. As per the 'SO_REUSEADDR and SO_REUSEPORT Socket Options' section in chapter 7.5 of Stevens' UNIX Network Programming Volume 1 (2nd Ed): "With TCP, we are never able to start multiple servers that bind the same IP address and same port: a completely duplicate binding. That is, we cannot start one server that binds 198.69.10.2 port 80 and start another that also binds 198.69.10.2 port 80, even if we set the SO_REUSEADDR socket option for the second server." So, it seems at least Windows isn't adhering to this, at least on XP and Server 2008 with 2.5-2.6. I've patched test_socket.py to explicitly test for this situation -- as expected, it passes on Unix (tested on FreeBSD in particular), and fails on Windows. I'd like to commit this to trunk to see if any of the buildbots for different platforms match the behaviour of Windows. ---------- assignee: Trent.Nelson components: Library (Lib), Windows files: test_socket.py.patch keywords: 26backport, patch messages: 64933 nosy: Trent.Nelson priority: high severity: normal status: open title: SO_REUSEADDR doesn't have the same semantics on Windows as on Unix type: behavior versions: Python 2.5, Python 2.6, Python 3.0 Added file: http://bugs.python.org/file9939/test_socket.py.patch __________________________________ Tracker <[EMAIL PROTECTED]> <http://bugs.python.org/issue2550> __________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
