hmm... I've been browsing the forum for 15 minutes and ran into this term a couple of times already! it seems like something i've got to know about :) any documents or tutorials on this subject?

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I highly recommend Network Programming for Microsoft Windows, Second Edition by Anthony Jones and Jim Ohmund.

Kuphryn

I second this recommendation. The book is really great.

Also, you might want to check CodeProject network section and look for "IOCP" or "Completion Port" articles.

Gizz