WSAIoctl

int WSAIoctl(
       SOCKET s,
       DWORD dwIoControlCode,
       void *  lpvInBuffer,
       DWORD cbInBuffer,
       void *  lpvOutBuffer,
       DWORD cbOutBuffer,
       DWORD *  lpcbBytesReturned,
       OVERLAPPED *  lpOverlapped,
       void *  lpCompletionRoutine
   )

Retrieve extension function pointer from Winsock.

Used to load AcceptEx, ConnectEx, and other extension functions.

Parameters

`s`	Socket descriptor.
`lpvInBuffer`	GUID of the function to retrieve.
`cbInBuffer`	Size of the GUID.
`lpvOutBuffer`	Receives the function pointer.
`cbOutBuffer`	Size of the output buffer.
`lpcbBytesReturned`	Receives actual bytes returned.
`lpOverlapped`	Overlapped structure (usually null for this call).
`lpCompletionRoutine`	Completion routine (usually null).

Returns

0 on success, SOCKET_ERROR on failure.