joyent/libuv — comment on commit c0792e54052bd3222c3b00e45f7e81c87187504a
File:  line 0
By phasis68:

Hi,

Calling setsockopt with IPPROTO_TCP and TCP_KEEPALIVE on Windows does not setting keep-alive timeout.
it just enable or disalbe TCP keep-alive option.
To set the keep-alive timeout, you must call WSAIoctl with SIO_KEEPALIVE_VALS and tcp_keepalive struncture.

Refer to http://msdn.microsoft.com/en-us/library/windows/desktop/dd877220(v=vs.85).aspx
http://pgbouncer.sourcearchive.com/documentation/1.4/socket_8h_aa4bb40aa83a8fa42bfa5dff63c46c0fc.html