Winsock Application Development

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Windows Embedded CE 6.0 R3


Windows Sockets (Winsock) is a programming interface that is based on the familiar socket interface from the University of California at Berkeley. Winsock includes extensions designed to take advantage of the message-driven nature of Windows Mobile, and is used to discover and use communications capabilities of underlying transport protocols.

Most Windows Mobile network communication passes through the Winsock interface. Windows Mobile Version 5.0 and later support Winsock 2.2, which provides easier access to multiple transport protocols.

A socket enables network applications to access data on a data network. A computing device may have only one physical connection to a network, but many sockets can use the one physical connection simultaneously.

Winsock client and server applications provide endpoints of communication for network applications. A server application executes, then it waits to receive a packet from the client application. Once communication is established, client and server applications can exchange data. A server application can handle multiple clients simultaneously.


Winsock client and server applications must be of the same socket type to communicate. For example, they must both be using byte stream sockets that use TCP, or they must both be using unreliable datagram sockets that use UDP.

In This Section

  • Winsock 2.2
    Provides information about Winsock 2.2 support in Windows Mobile, including the architecture, multiple transport protocols, overlapped I/O and event objects, name resolution, backward compatibility, and secure sockets. Also provides information about stream socket applications, User Datagram Protocol (UDP) Datagram Socket application, and Internet Protocol (IP) Multicast application, and creating an Infrared Winsock application.
  • Stream Socket Application
    Describes how to create a socket server, a socket client, and socket server and socket client applications.
  • Winsock Service Provider Interface (SPI)
    Provides information about the Winsock service provider interface (SPI), including socket creation and descriptor management, event objects, notification of network events, socket connections, socket I/O, shared sockets, and name resolution.
  • Raw Sockets
    Provides information about raw sockets support in Windows Mobile.