WebTcpipRecvPackets Function

Action

Receives individual or multiple in-coming packets from an open connection. A packet is defined as a TCP/IP packet or a part of an in-bound data stream that is separated by a specific packet boundary.

Include file

WebAPI.bdh

Syntax

WebTcpipRecvPackets(    in  hWeb             : number,
                        out sRecv            : string optional,
                        in  iPackets         : number optional,
                        out uPacketsReceived : number optional,
                        out iBytesReceived   : number optional ): boolean;

Return value

true if the operation was successful (connection did not break down or time out).
false otherwise

Parameter	Description
hWeb	Valid handle to a Web connection created by WebTcpipConnect.
sRecv	Output buffer for data that has been received (optional).
iPackets	Number of packets to be received (optional). When this parameter is omitted only one packet is received (default).
uPacketsReceived	The number of received packets is placed in this parameter (optional). Except in instances where the connection was closed or broken, this should equate to iPackets.
iBytesReceived	Sum of all received data is put into this numeric variable if passed as a parameter (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;