Creating A TCP Client

Hi, This sample is to showing you how to create quikely a  TCP client for UT2003. - Matthieu29 -

The "TCP" class:

It will send to an external progam, some text messages. I created this code to let's know in real time the status of the game by an external application.

For infos: For my personal usage, all messages get a "line feed" caracter at the end but, for general purpose, it's not needed.

The client have to connect to a server, so we set the server's port thanks to the default property variable "RemotePort". The server's address can be set too.

Class MyTcp extends TcpLink;

var int  RemotePort;    // Port of the server to connect
var char ServerAddress  // Address of the server to connect
var string LF;          // Used for linefeed "\n" 

//------------------------------------------------------------------------------

// First function called (init of the TCP connection)
Function InitTcpLinkEventLogger()
 {
 LF = Chr(10); // Line feed char "\n"

 Log("InitTcpLinkEventLogger: Will start TCP connection!");

 Resolve(ServerAddress);   // Resolve the address of the server
}                     

//------------------------------------------------------------------------------

Function Cclose() // Closes the current connection.
{
 Close();
}

//------------------------------------------------------------------------------

Function int SendText (coerce string Str)  // Send the string "Str" + "line feed" car
{
 local int result;

 result = super.SendText(Str$LF);  // Call the super (send the text)
 Log ("SentText: " $Str$" , (Number of bytes sent: "$result$")");
 return result;
}

//--EVENTS--

// Called when the IP is resolved
Event Resolved( IpAddr Addr )
{
  Log("OK, Address resolved");
  Addr.Port = remotePort;
  BindPort();         // In UnrealTournament, the CLIENT have to make a bind to create a socket! (Not as a classic TCP connection!!!)

  ReceiveMode = RMODE_Event;  // Incomming messages are triggering events
  LinkMode = MODE_Text;       // We expect to receive texts (if we receive datas)
  Open(Addr);                 // Open the connection

  Log ("Connected => Port :"$Addr.port$" Address :"$Addr.Addr);
}

//------------------------------------------------------------------------------

// If the IP was not resolved...
Event ResolveFailed()
{
  log("### Error, resolve failed!!!");
}

//------------------------------------------------------------------------------

event Opened()
{
  log("Ok, connection opened");
}

//------------------------------------------------------------------------------

// If somebody has close the connection...
Event Closed()
{
  log("Connection closed");
}

//------------------------------------------------------------------------------

// Called when a string is received
Event ReceivedText (string Text)
{
  // We have just received a string !
  Log("Read string: "$Text$" Size : "$Len(Text));
}

//------------------------------------------------------------------------------

defaultproperties
  {
  ServerAddress="127.0.0.1"  // Remote server address
  remotePort=3850            // Remote port number
  }

Ok, now how to use it:

• Create a MyTCPLink class
• Call InitTcpLinkEventLogger()
• Call SendText("A beautifull string")
• Call Cclose()

ReceivedText() is called when you receive some datas (I didn't tested this part of code, but there is no reasons it dosen't works)

// Somewhere in a class.....

var MyTcp ATcp;  


simulated event PostBeginPlay()
  {
  Super.PostBeginPlay();          // call the super class
  ATcp=Spawn(class'MyTcp'); // Instanciate MyTCP class
  ATcp.InitTcpLinkEventLogger();  // Init the connection
  }

[...]

// Somewhere in a function in this class...
ATcp.SendText ("Hello word");    // The classic !