A preliminary patch is in attachment.
By default it uses select() but looks for ValueError (raised in case FD_SETSIZE gets hit) and falls back on using poll().

This is the failure I get when running tests on Linux.
It is related to issue 3321 and I'm not sure what to do with it (remove the test maybe?).


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FAIL: test_invalid_handles (__main__.TestInvalidHandle)
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Traceback (most recent call last):
  File "Lib/test/test_multiprocessing.py", line 2852, in test_invalid_handles
    self.assertRaises((ValueError, IOError), conn.poll)
AssertionError: (<class 'ValueError'>, <class 'OSError'>) not raised by poll