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)