CompuServe Adds Value to Your Apps
May 9, 1995
In an age of application suites, groupware, and software bundling, what can increase the connectivity and data-acquisition capability of smaller applications?
One answer is to include application extensions in an extensive online environment such as CompuServe. Although the Developer Network has long had a presence on CompuServe, many developers may not have considered adding connectivity to CompuServe to enhance their applications. An online service can add value to most applications in numerous ways, such as the ability to obtain stock quotes for a financial application or to gather news stories for a personal information manager.
CompuServe offers two simple ways to add this connectivity to your applications without having to write an online interface from scratch.
The first is the CompuServe Communications Toolbox (CCT), a set of tools utilizing CompuServe's Host Micro Interface (HMI) that allows developers to build micro applications for connecting to the CompuServe Information Service (CIS). Although the Toolbox's primary function is to enable micro applications to establish HMI sessions with CIS through the connect functionality of CCT, it can also be used simply to access any host on the CompuServe network.
The second is the CompuServe Multimedia Publisher Partnership Program, which allows developers of multimedia CD-ROM products to add value to content by integrating their CD-ROM with access to the CIS.
CompuServe Communications Toolbox
By utilizing the CCT, a developer can interact with CompuServe in a defined, predictable manner. The underlying HMI protocol the Toolbox uses presents application protocols to all CompuServe host applications, such as forums or e-mail.
This protocol uses a structured data format, with an error-checking transport layer, to present the micro application with information that can be handled directly from within your existing user interface. This interface control flexibility means that you don't have to redesign the look and feel of your project to accommodate this new functionality. The CCT also provides the necessary low-level interaction for an application, so that everything from memory allocation and serial communications to data validation can be accomplished directly with a call to the Toolbox.
Many performance and compatibility requirements were incorporated in the design of the CCT. The Toolbox itself is fully ANSI-compatible, C++ callable, and compiled in various combinations of environments, compilers, and memory models.
Wherever possible, dialog boxes give a standard user interface to the Toolbox. Functions and dialog boxes are provided for obtaining serial communications settings, which consist of hardware parameters and a modem database to select parameters, as well as status boxes for displaying messages sent from the Toolbox.
These dialog boxes work in conjunction with CompuServe's predefined settings file format for common file access among multiple CompuServe applications. This file is used by all CompuServe applications to store the communications parameters that allow them to connect to CompuServe. If a function is platform-specific, the supported platform is listed in the declaration of the function.
Using the SendMessage function allows multitasking environments, such as Windows, a native way to interact with the Toolbox. In environments such as MS-DOS, the SendMessage function provides a single interface for the many functions in which the Toolbox must interact with the application.
The Toolbox also allows multiple applications to access it simultaneously. In the Windows environment, this means that all applications using the Toolbox can share a single dynamic-link library (DLL) without chance of interference. (In environments other than Windows, this may not be a requirement of the application.)
Because the library can be shared at run time in some environments (for example, Windows), a numeric naming scheme for the Toolbox is used that allows CompuServe to guarantee compatibility between new releases of the library. If at any point the libraries become incompatible with the previous version, the numeric portion of the filename will change (for example, CCT110 might supersede CCT100).
Hot links for multimedia
The new CompuServe Multimedia Publisher Partnership Program lets multimedia developers add various capabilities to their applications without increasing development time. The program permits inclusion of hypertext documents that link to various CIS locations.
It also allows users to perform such actions as electronic registration and transaction processing, and even to use CompuServe as a vehicle to communicate with their company for support. This gives the normally static medium of CD-ROM a new kick. The links can be used for something as simple as a weather report or for something more intensive, such as a downloadable patch or update area.
You can even use these hypertext links to Internet services through CompuServe. As part of this program, you can also license customized versions of other CompuServe software products, such as WinCIM or MacCIM, to include on your CD-ROM. (WinCIM is an application that serves as a graphical front end to CompuServe. WinCIM provides icons that let users jump easily and quickly into the developer-related areas of the Microsoft Connection area on CompuServe.)
Further information
The CCT and CompuServe Multimedia Publisher Partnership Program are both available for developers on the Windows 3.x, Windows for Workgroups 3.x, MS-DOS, GEOS, and Macintosh platforms. Support for Win32 development is planned this summer. For information about these or other CompuServe developer programs, contact:
Brian Glowacki
Phone: (614) 538-3379
Internet: glow@csi.compuserve.com
CIS: cis:glowThe Developer Network Development Library includes information on joining the CompuServe Information Service. For more information on CompuServe, call (800) 848-8990 from within the United States, or (614) 529-1340 outside the United States.