Microsoft KB Archive/35757

From BetaArchive Wiki

Using SHARE.EXE on MS-DOS Version 4.0 on Large Media PSS ID Number: Q35757 Article last modified on 01-19-1993 PSS database name: O_MSDOS

4.00

MS-DOS

The information in this article applies to:
- Microsoft MS-DOS operating system version 4.0

Summary:

If you are using MS-DOS version 4.0 with a large partition (greater than 32 megabytes), you should run SHARE.EXE in your AUTOEXEC.BAT or use INSTALL to run SHARE.EXE in your CONFIG.SYS.

More Information:

If you have a disk that is greater than 32 megabytes in size and you do not load SHARE.EXE, MS-DOS will issue the following warning:

WARNING! SHARE should be loaded for large media

This warning is issued for support of FCBs (file control blocks) in MS-DOS version 4.0 on large media. Applications that use FCBs have a fixed data structure that defines the FCB. Instead of changing the structure of the FCB to address large media (which would make all existing FCB software unusable), MS-DOS version 4.0 requires that SHARE.EXE to be loaded. When SHARE.EXE is loaded, an internal file system table is used by the operating system on top of the application’s FCB structure, which allows the operating system to handle the different size of the FCB structure.

Programs that use file handles don’t cause this problem because, unlike FCBs, the data structure for a file handle is maintained by the operating system, not the application.

Loading SHARE.EXE is not needed with MS-DOS 5.0. The FCB-to-file- handle translation is done in the kernel.

Additional reference words: 4.00 noupd

Copyright Microsoft Corporation 1993.