UdpSend

The procedure shown in Figure 1 sends a UDP datagram to the specified foreign socket. The source socket is the local socket selected in the UdpOpen that returned the ConnIndex value that was used. The buffer does not include the UDP header. This header is supplied by TCP/IP.

When there is no buffer space to process the data, an error is returned. In this case, wait for a subsequent UDPdatagramSPACEavailable notification.

Figure 1. UdpSend example

   procedure UdpSend
            (
                 ConnIndex: ConnectionIndexType;
                 ForeignSocket: SocketType;
                 BufferAddress: integer;
                 Length: integer;
        var    ReturnCode: CallReturnCodeType
            );
            external;

Parameter

Description

ConnIndex

The ConnIndex value returned from UdpOpen.

ForeignSocket

The foreign socket (address and port) to which the datagram is to be sent.

BufferAddress

The address of your buffer containing the UDP datagram to be sent, excluding UDP header.

Length

The length of the datagram to be sent, excluding UDP header. Maximum is 65507 bytes.

ReturnCode

Indicates success or failure of a call. Possible return values are:

OK
BADlengthARGUMENT
NObufferSPACE
NOsuchCONNECTION
NOTyetBEGUN
SOFTWAREerror
TCPipSHUTDOWN
UDPunspecADDRESS
UDPunspecPORT
INVALIDvirtualADDRESS

For a description of Pascal return codes, see Table 1.