Sharing Windows-Based Applications Across Networks

The information in this article applies to:

• Microsoft Windows Software Development Kit (SDK) for Windows versions 3.0 and 3.1

When writing Windows-based applications that may be placed on a network, it is necessary to consider the demands of the MS-DOS SHARE utility and of the network when designing the application.

If the application is written to conform to the normal MS-DOS INT 21H protocol and the network supports shared access, then the application will run properly. Most network vendors implement some kind of file sharing system that handles multiple files accessed across the network.

In many cases, network applications are not tested properly. It is necessary to test the worst-case scenario, where the same file is opened by more than one workstation simultaneously and manipulated using standard file I/O instructions (read, write, close, and so forth).

When the MS-DOS SHARE utility is run from a workstation, only the files on that workstation are shared. However, if SHARE is not run on the network server, applications will encounter problems. All Microsoft LAN Manager servers load SHARE so that file sharing is virtually transparent to the user. It is the user's responsibility to verify the network's implementation of shared files.

The "IBM DOS Technical Reference" shows the normal file operations table. This should be used as the guideline when network applications are implemented.