SysSockRecvFrom (FUN)¶

FUNCTION SysSockRecvFrom : __XINT

Receive a message from a connectionless socket (UDP).

NOTE: With some IP stacks (LwIP for example, which is used with the CODESYS Control RTE), it is necessary to set the SOCKET_SO_BROADCAST socket option (SOCKET_SOL level) in order to be able to receive broadcast UDP messages with the SysSockRecvMsg() and SysSockRecvFrom() functions.

InOut:

Scope	Name	Type	Comment
Return	`SysSockRecvFrom`	`__XINT`	Number of bytes received
Input	`hSocket`	`RTS_IEC_HANDLE`	Handle to the socket
	`pbyBuffer`	POINTER TO BYTE	Buffer to read data from the socket
	`diBufferSize`	`__XINT`	Maximum length of the buffer
	`diFlags`	`DINT`	The flags parameter can be used to influence the behavior of the function beyond the options specified for the associated socket. The semantics of this function are determined by the socket options and the flags parameter. The latter is constructed by using the bitwise OR operator with any of the SOCKET_MSG values.
	`pSockAddr`	POINTER TO SOCKADDRESS	Socket address and port to receive data from
	`diSockAddrSize`	`DINT`	Size of socket address structure
	`pResult`	POINTER TO RTS_IEC_RESULT	Pointer to runtime system error code (see CmpErrors.library)