If socket timeout > 0, then there is no way to automatically
restart some socket calls like recv().
Calling siginterrupt(False) is useless, because python calls
internal_select() if socket has timeout, and select returns
error(EINTR) once interrupted by a signal, regardless of the
SA_RESTART flags.

So a user may have to wrap every socket calls in this case.

I found some related discussions in http://bugs.python.org/issue7978

Extract of manpage signal(7):

"The following interfaces are never restarted after being interrupted by a signal handler, regardless of the use of SA_RESTART; they always fail with the error EINTR when interrupted by a signal handler:

• ...
• File descriptor multiplexing interfaces: epoll_wait(2), epoll_pwait(2), poll(2), ppoll(2), select(2), and pselect(2)."

Consider siginterrupt(signal, False) as a "best-effort" trick... which doesn't work with select().

If you don't want select() to be interrupted by SIGINT, use:

pthread_sigmask(SIG_BLOCK, [SIGINT]);
select(...)
pthread_sigmask(SIG_UNBLOCK, [SIGINT])

or

pselect(...., [SIGINT])

pselect() is atomic, whereas pthread_sigmask+select is not.

I added recently pthread_sigmask() to the signal module in Python 3.3.

pselect() is not exposed in Python currently. We may add it if it's needed.

--

If you really don't care of SIGINT, you can also ignore it completly using signal(SIGINT, SIG_IGN).

Victor, I understand your response as saying that there is no bug, which would suggest closing this. Correct? If not, what is the requested action?

Actually, it's part of a more general problem with EINTR being returned by many posix/socket module functions, see for example issue bpo-7978.
On the one hand, having to retry manually on EINTR is cumbersome, on the other hand, some code might rely on this - receiving EINTR - and the posix module policy is to expose syscalls as-is.
This should probably be closed as duplicate of issue bpo-9867.

Victor, I understand your response as saying that there is no bug,
which would suggest closing this. Correct? If not, what is
the requested action?

siginterrupt(False) has no effect on select().

I listed some solutions to not interrupt select() on a signal (avoid completly EINTR). Issues bpo-7978 and bpo-9867 try the other solution, handle EINTR (retry select() on EINTR). I think that most users prefer the later (handle EINTR), so let's close as a duplicate.

@zhiping Deng: Reopen the issue if you want the first solution :-)

I think the problem is that after a user calles signal.siginterrupt(False),
he would expect that the socket.recv should handles EINTR properly
for him because it's the behaviour in c level.
He doesn't know socket.recv() calles select(2) internally and he needn't.

Or at least this should be documented in signal.siginterrupt().