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Somebody in the thread at some point said:
> Andy Green wrote,
>> Why don't you try removing the O_NONBLOCK since you test with
>> select...
> 
> Never, ever, do that ... select only returns a hint that an IO operation 
> might succeed, not a guarantee (google for "spurious wakeup"), hence a 
> subsequent read/write might block if the descriptor isn't set to 
> O_NONBLOCK, and that's almost always not what's wanted or expected.

Wah, man select says it too

       Under  Linux,  select()  may  report  a  socket file descriptor
as "ready for reading", while nevertheless a subsequent read
       blocks. This could for example happen when data has arrived but
upon examination has wrong checksum and is discarded.  There
       may  be  other circumstances in which a file descriptor is
spuriously reported as ready.  Thus it may be safer to use O_NON-
       BLOCK on sockets that should not block.

Pretty freakish, thanks for the tip.

-Andy


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