WSASetUdpSendMessageSize function (ws2tcpip.h)

Sets the segmentation message size on a UDP socket.


INT WSASetUdpSendMessageSize(
  [in] SOCKET Socket,
  [in] DWORD  MsgSize


[in] Socket

A descriptor that identifies a UDP socket.

[in] MsgSize


The message size to be set on the socket for UDP segmentation.

Return value

On success, the function returns 0. Otherwise, a value of SOCKET_ERROR is returned, and you can retrieve a specific error code by calling WSAGetLastError.


UDP send segmentation is supported through the UDP_SEND_MSG_SIZE socket option. WSASetUdpSendMessageSize is a type-safe wrapper for setting this socket option, and we recommend it over setsockopt.


Minimum supported client Windows 10, version 2004 (10.0; Build 19041)
Minimum supported server Windows Server, version 2004 (10.0; Build 19041)
Target Platform Windows
Header ws2tcpip.h
Library Ws2_32.lib
DLL Ws2_32.dll