RawIpSend

This procedure shown in this example sends IP datagrams of the given protocol number. The entire packet, including the IP header, must be in the buffer. The TCP/IP address space uses the total length field of the IP header to determine where each packet ends. Subsequent packets begin at the next doubleword (eight-byte) boundary within the buffer.

The packets in your buffer are transmitted unchanged with the following exceptions:

They can be fragmented; the fragment offset and flag fields in the header are filled.
The version field in the header is filled.
The checksum field in the header is filled.
The source address field in the header is filled.

You get the return code NOsuchCONNECTION if the client is not handling the protocol, or if a packet in the buffer has another protocol. The return code BADlengthARGUMENT is received when:

The DataLength is fewer than 40 bytes, or greater than 65535 bytes.
NumPackets is 0.
All packets do not fit into DataLength.

A ReturnCode value of NObufferSPACE indicates that the data is rejected, because TCP/IP is out of buffers. When buffer space is available, the notification RAWIPspaceAVAILABLE is sent to the client.

Figure 1. RawIpSend example

   procedure RawIpSend
            (
                 ProtocolNo: integer;
                 Buffer: Address31Type;
                 DataLength: integer;
                 NumPackets: integers;
        var    ReturnCode: integer
            );
            external;

Parameter

Description

ProtocolNo

The number of the Internet protocol.

Buffer

The address of your buffer containing packets to send.

DataLength

The total length of data in your buffer.

NumPackets

The number of packets in your buffer.

ReturnCode

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

OK
BADlengthARGUMENT
NObufferSPACE
NOsuchCONNECTION
NOTyetBEGUN
SOFTWAREerror
TCPipSHUTDOWN
UNAUTHORIZEDuser
INVALIDvirtualADDRESS

Note: If your buffer contains multiple packets waiting to be sent, some of the packets might have been sent even if ReturnCode is not OK.

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