Windows Sockets Direct Extensions
A SAN service provider DLL implements the Windows Sockets Direct extension functions to extend Windows Sockets SPI for use with a system area network (SAN).
Note These Windows Sockets Direct extension functions are defined in Ws2san.h and require Windows Sockets version 2.2.
To support the Windows Sockets switch, a SAN service provider must implement all these extension functions (except the optional WSPRdmaReadand WSPMemoryRegistrationCacheCallbackfunctions). If a SAN service provider does not support either the WSPRdmaReador WSPMemoryRegistrationCacheCallbackextension function, its WSPIoctlfunction must return the WSAEOPNOTSUPP error code after the switch requests a pointer to WSPRdmaReador WSPMemoryRegistrationCacheCallback.
See the following topics for more information about the Windows Sockets Direct extension functions:
WSPMemoryRegistrationCacheCallback