{
 This program sends packets between two users logged in
 to the same server.  This program is meant to be an example
 of how to send IPX packets over an IPX network and is not
 meant to be an actual utility.}
program send;
uses crt,ipx;

const
 receive_socket = $7777; {Arbitrary socket numbers are chosen}
 send_socket = $6666;

procedure abort(message:string);
begin
 writeln(message);
 halt(1);
end;

var
 connection_number:word;
 network_number:networkNumber;
 network_node:networkNode;
 receive_ecb,send_ecb:ECB;
 receive_header,send_header:IPXHeader;
 receive_message,send_message:MessageSTR;
 done,stop : boolean;

 begin
  {Make sure IPX is installed, otherwise don't continue}
  if not IPXinstalled then abort('IPX not loaded');

  {Get the username from the command line, and use it to get the users
   connection number}
  connection_number := Get1stConnectionNumber(paramstr(1));
  {0 is returned, if the user isn't logged in}
  if connection_number = 0 then abort(paramstr(1) + ' not found. ');

  {Use the connection number obtained from above to get the users address}
  if GetINternetAddress(connection_number,network_number,network_node) <> 0
      then abort(paramstr(1) + 'network error.');

  {Initialize IPX sockets for communication}
  IpxCloseSocket(send_socket);
  if IPXOpenSocket(send_socket) <> 0 then abort('Socket error.');
  IPXCloseSocket(receive_socket);
  if IPXOpenSocket(receive_socket) <> 0 then abort('Socket error.');

{The chat program}
stop := false;
writeln('Attempting to enter chat (^ to stop)');
while (receive_message <> 'ack') and (not stop) do
 begin
  if keypressed then
   if readkey = '^' then stop := true;
  send_message := 'ack';
  IPXSend(network_number,
          network_node,
          receive_socket,
          @send_message,
          length(send_message)+1,
          send_ecb,
          send_header,
          send_socket);

  IPXReceive(receive_ecb, receive_header, receive_socket,
             @receive_message, sizeof(receive_message));
 end;

if stop = true then
 else
  begin
  writeln('Entering Chat mode: type ^ to exit');
  done := false;
  repeat
   if (receive_ecb.completion_code = 0) and (receive_ecb.in_use = 0)
        then
         begin
          textcolor(lightgreen);
          write(receive_message);
          if receive_message=chr(13) then writeln;
          IPXReceive(receive_ecb, receive_header, receive_socket,
                      @receive_message, sizeof(receive_message));
         end;

   IPXRelinquishControl; {This line allows IPX time to process.
                          without this line your machine will NOT
                          send any packets out.}
   if KeyPressed
    then
     begin
      send_message := '';
      send_message := ReadKey;
      textcolor(yellow);
      write(send_message);
      if send_message=chr(13) then writeln;
      IPXSend(network_number,
              network_node,
              receive_socket,
              @send_message,
              length(send_message)+1,
              send_ecb,
              send_header,
              send_socket);
     end;
   if (send_message = '^') or (receive_message= '^') then
    begin
     writeln('Exiting Chat mode');
     done := true;
     IPXCloseSocket(send_socket);
     IPXCloseSocket(receive_socket);
    end;
  until done;
 end;
 end.


     IPXCloseSocket(send_socket);

     IPXCloseSocket(receive_socket);

    end;

  until done;

 end;

 end.