1.5 How LANSA Open Works

Your PC based application can be developed using Visual Basic, Paradox, Delphi, Gupta, PowerBuilder, Excel, REXX, C or in fact any PC development tool that can reference a third party DLL.

• The application program makes calls to the LANSA Open functions which reside locally on the PC. This call may be to a function to format data, send information to the server or receive information from the server.

For example, if the application calls the LANSA Open function LceFetch (to get a record from the host), LANSA Open sends a request for data to the server.

• On the server, a LANSA Open program receives the request and determines what action to take.

If a file needs to be accessed, the appropriate LANSA OAM (or I/O Module) is called and the data is retrieved and formatted.

• Once the data is retrieved, it is transmitted back to the PC.

• The PC application can then use other LANSA Open functions to access that data which is stored on the PC.

Note that if you are programming using any language that targets the .NET runtime (e.g. C#, VB.NET), you should use LANSA Open for .NET instead of LANSA Open.
The use of LANSA Open from .NET languages is NOT recommended due to incompatibility with .NET strings – manual conversion is required when passing .NET strings.