• The UDP protocol
  • Operating mode of UDP sockets
  • Limitation
  • Required permissions
WindowsLinuxUniversal Windows 10 AppJavaReports and QueriesUser code (UMC)
WindowsLinuxPHPWEBDEV - Browser code
AndroidAndroid Widget iPhone/iPadIOS WidgetApple WatchMac CatalystUniversal Windows 10 App
Stored procedures
Creates a socket that is using the UDP protocol.
WEBDEV - Server code To use sockets on the server, "Allow the server sockets" must be checked in the WEBDEV administrator.
IF SocketCreateUDP("Server", 8000) = False THEN
Error("Creation error" + ErrorInfo(errMessage))
<Result> = SocketCreateUDP(<Socket name> , <Port number> [, <Address>])
<Result>: Boolean
  • True if the function was successful,
  • False otherwise. If an error occurs, you can get more details on the error with ErrorInfo.
<Socket name>: Character string
Name that will be given to the socket. This name will be used by all socket functions.
Caution: the socket name is case sensitive.
<Port number>: Integer
Port number that will be given to the socket. This number must be included between 5000 and 65000. This number will be specified when the client computers are connected to the server.
<Address>: Optional character string
IP address on which the socket must be created on the current computer. If the current computer is associated with several IP addresses (or with several network cards), this parameter enables you to choose the IP address that will be associated with the socket.
This IP address can have the following format:
  • IP address in XXX.XXX.XXX.XXX format ( for example).
  • IP address containing the name of the server ( for example). This syntax is recommended.
  • IP address returned by NetIPAddress.

The UDP protocol

When using UDP sockets, there is no notion of connection (as opposed to TCP sockets that are connection-oriented). UDP is a connectionless protocol.
All the UDP sockets, no matter whether they are client sockets or server sockets, are created by SocketCreateUDP.
When a write operation is performed via the UDP protocol, you must specify the destination (address and port).
When a read operation is performed via the UDP protocol, the origin of the string read is unknown. It is returned by SocketClientInfo.
Remark: The UDP protocol is a connectionless protocol, there is no guarantee that the information sent was received.

Operating mode of UDP sockets

A port already opened by another application can be re-opened. The port will be closed during the call to SocketClose or when ending the application that opened it.
LinuxAndroidAndroid Widget iPhone/iPadIOS WidgetMac Catalyst


You must be "root" to create a socket on a port less than or equal to 1024 (being "root" means being the user who has all the permissions on the system).
AndroidAndroid Widget

Required permissions

The call to this function modifies the permissions required by the application.
Required permission : INTERNET
This permission allows the applications to open the network sockets.
Component: wd280com.dll
Minimum version required
  • Version 9
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