SelectSelector._select is differently on different platforms.

On win32, SelectSelector._select is a unbound/bound method and pass instance as the first argument, but on *nix, SelectSelector._select is a builtin_function_or_method(Although self.select still works)

If someone want to replace(or patch) select, he must implement two select function(one is a function, the other is a instance method), 
Otherwise you will get「TypeError: select() takes at most 4 arguments (5 given)」.

And I think make built-in funtion(like len, select.select) as a class attr/method is a black magic(it's still a function) and hard to maintain

Thanks for the report! This is a duplicate of issue 27634.

Since we got multiple reports [1][2] about the same problem on selectors34 (backport of selector module) and use of Gevent is very popular, I think we should reconsider the idea of wrapping select.select with staticmethod().

Also, if I remember correctly, this was fixed on Gevent's side before (although I know that you didn't mention Gevent in your report)

Victor and Charles-François, what do you think?

[1] https://github.com/berkerpeksag/selectors34/pull/4
[2] https://github.com/berkerpeksag/selectors34/issues/5

Thx for your replying, Peksag.

I encountered this problem is really because of Gevent and Selector34. Gevent fixed this issue but only works for python3.4+(https://github.com/gevent/gevent/blob/master/src/gevent/monkey.py#L497) by a tricking way. python 2.x still has this problem

Great! Since this is no longer an issue on Python 3.4+, I'm going to close this as a duplicate of issue 27634 and merge https://github.com/berkerpeksag/selectors34/pull/4.

I know it works on python3.4, but black magic still exists in selectors lib，and 3rd-party module have to prepare two function to make compatibility.