Legacy Integration - ActiveX /.NET 3270 and 5250 Middleware for Enterprise Integration

PASSPORT Host Integration Objects -- Programming Questions

ActiveX and .NET 3270 and 5250 Host Integration

What objects are available?

The following objects are provided. The objects are structured in a hierarchical manner.

• Sessions Object - Contains one or more Session objects.
• Session Object - Contains one Screen object.
• Screen Object - Contains one Fields object and one OIA object.
• Fields Object - Contains one or more Field objects.
• Field Object - The fundamental element of a virtual host screen.
• OIA Object - The Operator Information Area (status line) object.
• Terminal Control - Runs in conjunction with a session object. Provides a user interface for that session object.

What programming languages can I use?

Any Microsoft or other programming language that can use ActiveX components or .NET managed code can be used with the PASSPORT Host Integration Objects. These include Visual C++, Visual Basic, Visual FoxPro, VB Script, Script, ASP, ASP .NET, Visual C++ .NET, Visual Basic .NET, Visual C# .NET, Visual J# .NET, Cobol, Fortran and many others.

Is Microsoft .NET supported?

Yes, Microsoft .NET is supported.

Is sample source code included?

Yes, sample source code is included. There are VB .NET, Visual Basic, VB Script, C++ and C# .NET sample programs included with the PASSPORT Host Integration Objects.

Are there event driven functions?

Yes, there are event driven functions. The Session object includes the following events:

• OnSessionChanged
• OnScreenChanged
• OnOIAChanged

What are the memory requirements?

The first session launched requires 280KB of memory. Each additional session launched requires 90KB of memory. This is in addition to the memory your application requires.

What diagnostic tools are available?

There are two types of diagnostic tracing capabilities:

• Low Level Tracing
• Data Stream Tracing

The low level tracing monitors all incoming and outgoing TCP/IP buffers at the WinSock layer. The data stream tracing monitors only the 3270 or 5250 data stream buffers.

Can I just link in a library file?

No, a .LIB library file is not provided at this time. You must access the PASSPORT Host Integration Objects as either an ActiveX COM object or .NET managed code.

How is this different from HLLAPI?

HLLAPI is an older non-object oriented host access interface that was developed in the mid 1980s originally for the DOS operating system. PASSPORT Host Integration Objects is based on OHIO, which is a newer object oriented host access interface. HLLAPI requires that a terminal emulator be loaded and active in memory, whereas PASSPORT HIO does not. Because of this, HLLAPI applications use much more memory and are not as scalable. Both HLLAPI and PASSPORT HIO provide similar functions to read and write virtual host screens.

Can I reuse my HLLAPI application?

It is possible to rewrite a HLLAPI application to use PASSPORT Host Integration Objects. Most HLLAPI functions do have an equivalent PASSPORT HIO method or property. However, there are some HLLAPI functions such as send/receive and the keystroke interface functions that do not. If you would like to discuss porting a HLLAPI application to a server application using the PASSPORT Host Integration Objects contact Zephyr at http://www.zephyrcorp.com/Info/contact_zephyr.asp.

How is this different from the PASSPORT Object interface?

The PASSPORT Object interface is also an object oriented host access interface. However, the PASSPORT Object interface requires that the PASSPORT PC TO HOST ® or PASSPORT WEB TO HOST ® terminal emulator be loaded and active. The PASSPORT Host Integration Objects does not require a terminal emulator to be loaded and active. The PASSPORT Object interface provides a Screen Area object instead of the Fields and Field objects provided with PASSPORT Host Integration Objects.