sendto

Asynchronous sending function, used to send data on a UDP socket.

Called by the application code when there is data required to be sent on a UDP socket handler. The application code is expected to receive data from a successful bounded socket node. The only difference between this function and the similar send function, is the type of socket the data is received on. This function works only with UDP sockets. After the data is sent, the socket callback function registered using registerSocketCallback(), is expected to receive an event of type SOCKET_MSG_SENDTO.

Functions
NMI_API sint16	sendto (SOCKET sock, void *pvSendBuffer, uint16 u16SendLength, uint16 flags, struct sockaddr *pstrDestAddr, uint8 u8AddrLen)

NMI_API sint16 sendto	(	SOCKET	sock,
		void *	pvSendBuffer,
		uint16	u16SendLength,
		uint16	flags,
		struct sockaddr *	pstrDestAddr,
		uint8	u8AddrLen
	)

Parameters

[in]	sock	Socket ID, must hold a non negative value. A negative value will return a socket error SOCK_ERR_INVALID_ARG. Indicating that an invalid argument is passed in.
[in]	pvSendBuffer	Pointer to a buffer holding data to be transmitted. A NULL value will return a socket error SOCK_ERR_INVALID_ARG. Indicating that an invalid argument is passed in.
[in]	u16SendLength	The buffer size in bytes. It must not exceed SOCKET_BUFFER_MAX_LENGTH.
[in]	flags	Not used in the current implementation
[in]	pstrDestAddr	The destination address.
[in]	u8AddrLen	Destination address length in bytes. Not used in the current implementation, only included for BSD compatibility.

Precondition

Sockets must be initialized using socketInit.

Warning

u16SendLength must not exceed SOCKET_BUFFER_MAX_LENGTH.
Use a valid socket (returned from socket ). A valid buffer pointer must be used (not NULL).
Successful completion of a call to sendto() does not guarantee delivery of the message, A negative return value indicates only locally-detected errors

See Also

socketInit recvfrom sendto socket connect accept send

Returns

The function returns SOCK_ERR_NO_ERROR for successful operation and a negative value (indicating the error) otherwise.

References m2m_memset(), M2M_REQ_DATA_PKT, MAX_SOCKET, NM_BSP_B_L_16, NULL, in_addr::s_addr, sockaddr_in::sin_addr, sockaddr_in::sin_family, sockaddr_in::sin_port, tstrSendCmd::sock, SOCK_ERR_BUFFER_FULL, SOCK_ERR_INVALID_ARG, SOCK_ERR_NO_ERROR, SOCKET_BUFFER_MAX_LENGTH, SOCKET_CMD_SENDTO, SOCKET_REQUEST, tstrSendCmd::strAddr, tstrSendCmd::u16DataSize, tstrSockAddr::u16Family, tstrSockAddr::u16Port, tstrSocket::u16SessionID, tstrSendCmd::u16SessionID, tstrSockAddr::u32IPAddr, and UDP_TX_PACKET_OFFSET.

Referenced by demo_start().