WebTcpipGetPacketBoundary Function

Action

Returns a packet boundary for an existing connection. The packet boundary is used to split in-coming and out-going data when using WebTcpipRecvPackets and WebTcpipSendPackets functions. By default a “packet” consists of a TCP/IP packet. So in effect, the packet boundary is set to NULL.

Include file

WebAPI.bdh

Syntax

WebTcpipGetPacketBoundary(    in  hWeb      : number,
                              out sBoundary : string ) : boolean;

Return value

true if the operation was successful
false otherwise

Parameter	Description
hWeb	Valid handle to a Web connection created by WebTcpipConnect.
sBoundary	String variable in which the current packet boundary is placed. By default a NULL string (a raw TCP/IP packet) is returned.

Example

dcltrans
  transaction TInit
  begin
    StrSetHostCP(28591); // 28591 (ISO 8859-1 Latin I)
  end TInit;
   
  transaction   TMain
  var
    hWeb0     : number;
    sBuffer   : string;
    sBoundary : string;
    nOption   : number;
  begin
    WebTcpipConnect(hWeb0, "My.TelnetHost.IP", WEB_PORT_TELNET);
    WebTcpipSetTelnetMode(hWeb0, TERMINAL_TYPE_ANSI, 80, 24, true, TELNET_MODEOPT_SYNC);
    WebTcpipGetOptions(hWeb0, nOption);
    if nOption <> TELNET_MODEOPT_RFC_1576 then
      WebTcpipSetOptions(hWeb0, TELNET_MODEOPT_RFC_1576);
    end;
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_TerminalType);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_TerminalSpeed);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_XDisplayLocation);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_NewEnvironment);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_WILL, TELNET_OPT_TerminalType);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_WONT, TELNET_OPT_TerminalSpeed);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_WONT, TELNET_OPT_XDisplayLocation);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_WONT, TELNET_OPT_NewEnvironment);
    WebTelnetRecvSubNegotiation(hWeb0, TELNET_OPT_TerminalType);
    WebTelnetSendTerminalType(hWeb0, "vt100");
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_WILL, TELNET_OPT_SuppressGoAhead);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_Echo);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_NegotiateWindowSize);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_WILL, TELNET_OPT_Status);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_RemoteFlowControl);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_DO, TELNET_OPT_SuppressGoAhead);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_WONT, TELNET_OPT_Echo);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_WILL, TELNET_OPT_NegotiateWindowSize);
    WebTelnetSendSubNegotiation(hWeb0, TELNET_OPT_NegotiateWindowSize, "\h00500018");
    WebTelnetSendCommand(hWeb0, TELNET_CMD_DONT, TELNET_OPT_Status);
    WebTelnetSendCommand(hWeb0, TELNET_CMD_WONT, TELNET_OPT_RemoteFlowControl);
    WebTelnetRecvCommand(hWeb0, TELNET_CMD_WILL, TELNET_OPT_Echo);
    WebTcpipGetPacketBoundary(hWeb0, sBoundary);    
    WebTcpipRecvPacketsUntilData(hWeb0, "login: ");
    WebTelnetTypeKeys(hWeb0, StrToHostCP("leo"), 359.3, TELNET_FLAG_CASE_SENSITIVE);
    WebTcpipSendBin(hWeb0, "\h0D00");
    WebTcpipRecvExact(hWeb0, NULL, 390);
    WebTcpipSetPacketBoundary(hWeb0, sBoundary);
    WebTcpipRecvUntilIdle(hWeb0, NULL, 5000);
    WebTcpipSendBin(hWeb0, "\h0D000D0A");
    WebTcpipRecvPackets(hWeb0, NULL, 3);
    WebTcpipSendBin(hWeb0, "\h0D00");
    WebTcpipSendPacket(hWeb0, StrToHostCP("8") + "\h0D00");
    WebTcpipRecvClose(hWeb0, NULL);
    WebTcpipShutdown(hWeb0);
  end TMain;