WebTelnetRecvSubNegotiation Function

Action

Receives a Telnet option sub-negotiation sequence from a terminal service server, which is a shortcut to IAC SB <Option> <Data> IAC SE.

Include file

WebAPI.bdh

Syntax

WebTelnetRecvSubNegotiation(    in  hWeb          : number,
                                in iOpt           : number optional,
                                in sDataExpected  : string optional,
                                out iOptReceived  : number optional,
                                in sDataReceived  : string optional ): boolean;

Return value

  • true if the operation was successful

  • false otherwise

Parameter Description
hWeb Valid handle to a Web connection created by WebTcpipConnect and set to Telnet mode using WebTcpipSetTelnetMode.
iOpt Optional Telnet sub-negotiation option that is expected from the server (optional). See constants in WebTelnetSendCommand for valid values. Set -1 when no validation is to be performed.
sDataExpected Binary sub-negotiation data string expected from the server (optional). Set to NULL if no validation is to be performed.
iOptReceived Optional variable where the sub-negotiation option received from the server is to be placed (optional).
sDataReceived Optional output string buffer where data received from the server is to be placed (optional).

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;