Comment 4 for bug 868349

It seems that os.open(..., os.O_NONBLOCK) nevertheless does block, so self.fd is not replaced. If ConsoleLogger.close() gets called at this point from another thread, then a double close is attempted. The fix for this is trivial, although I'm still baffled by how this is possible in eventlet. I also can't seem to be able to reproduce it in a test. However I have reproduced by hand, and have verified that the fix appears to work. The fix is also trivial enough that I'm confident it won't cause any other issues.