The first step in working with TrueGui is to setup your server and client to talk to each other thru TrueGUI and not directly. What you need to know before you get started is the server's IP address or host name, and its telnet port. The additional settings such as terminal driver would also need to be replicated for this exercise.
The local IP of the client can normally be communicated with by using the address 127.0.0.1. This address is a reserved IP address corresponding to the host computer. Known as the loopback address, 127.0.0.1 is used whenever a program needs to access a network service running on the same computer as itself. TrueGUI only handles IPv4 currently. You won't be able to connect to that local address until TrueGUI has established the connection to the server.
We need to add a profile or configuration file to your telnet client and launch it using those parameters. Below are a few examples of command lines that launch a telnet application from the command line. If your telnet client is not capable of doing this, it would be necessary to define the default profile to launch using the 127.0.0.1 connection.
Windows Telnet
C:\TELNET 127.0.0.1 8000
AlphaLan
C:\Program Files (x86)\UASystems\AlphaLAN++9.0\ALan.exe loopback.aln
or
C:\ALPAHALAN\Winorbit.exe 127.0.0.1 8000
ZTerm
C:\Program Files (x86)\COOL.STF\ZTERM for Windows\Zterm32.exe loopback.ztc
or
C:\Program Files (x86)\COOL.STF\ZTERM for Windows\Zterm32.exe 127.0.0.1:8000
Now using the TrueGUI.exe it is easy to implement these in the Passthru tab. First click on Select Telnet and browse to and select your telnet application. Add the underlined parameter above in the parameter field.
So once you have determined these parameters, its time to put it together so that one click takes you in as it would with your telnet client. This can be done using a desktop shortcut and startup parameters of TruGUI.exe. First make a copy of the TrueGUI shortcut on your desktop. Label this TrueGuiPassthru or you could call it your application name and change the default icon to that of your application.
As mentioned in the getting started you have the ability to startup TrueGUI.exe with command line parameters itself. Launch TrueGui.exe and set the passthru client parameters as mentioned above. Now go to the Startup tab and set the check boxes for use Passthru method, autostart, and start minimized. If your a developer you may want to also have the Debugger checked as well. In the settings group change the text box to "passthrusettings.cfg" and click save. Then exit TrueGUI.exe.
Lastly, we need to add the startup parameter to the shortcut you made on the desktop. Right click the shortcut you made on the desktop and add the startup parameter of -ipassthrusettings.cfg as shown below.
Passthru Sequence
Now that you have passthru working on your desktop, lets take a look at how we get TrueGUI to toggle between your telnet application and TrueGUI. Once the connection has been made to the server, TrueGUI is only looking for the sequence to take control. It is important to remind the developer that the sequence code be invoked by viewing your source code using a passthru connection. So having two connections to the server becomes useful.
Lets look at an example of server code:
BEGIN
PRINT "EnterTrueGuiMode"
PRINT "{ TrueGui.LoadAssembly(`CsForms`) }"
print "{ MyForm = New CsForms.Form1() }"
PRINT "{ MyForm.Show() }"
PRINT "LeaveTrueGuiMode"
END