| Platform SDK: Windows Sockets |
The Windows Sockets 2 specification defines an extension mechanism that exposes advanced transport functionality to application programs. For more information, see Function Extension Mechanism.
The following Microsoft-specific extensions were added to Windows Sockets 1.1. They are also available in Windows Sockets 2:
These functions are not exported from the Ws2_32.dll; they are exported from Mswsock.dll.
An application written to use the Microsoft-specific extensions to Winsock will not run correctly over a Windows Sockets service provider that does not support those extensions.