non blocking tcp connect with epoll

Posted by doccarcass on Stack Overflow See other posts from Stack Overflow or by doccarcass
Published on 2010-05-20T15:04:34Z Indexed on 2010/05/21 1:20 UTC
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tcp

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linux

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epoll

My linux application is performing non-blocking TCP connect syscall and then use epoll_wait to detect three way handshake completion. Sometimes epoll_wait returns with both POLLOUT & POLLERR revents set for the same socket descriptor. I would like to understand what's going on at TCP level. I'm not able to reproduce it on demand. My guess is that between two calls to epoll_wait inside my event loop we had a SYN+ACK/ACK/FIN sequence but again I'm not able to reproduce it. Any clue ?

Regards, Seb

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