FYI
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          TITLE:  DR DOS & DOS version numbers
   DOCUMENT ID#:  FYI-M-1600
           DATE:  04JAN93
        PRODUCT:  DR DOS
PRODUCT VERSION:  6.0
     SUPERSEDES:

        SYMPTOM:  Applications that check the DOS version number  
                  do not indicate 6.0 but 3.31.

  ISSUE/PROBLEM:
Device drivers for disk drives or networks are sometimes produced
for specific versions of DOS or occasionally will use specific
configurations for different versions of DOS. When applications
request the DOS version number from the operating system (via INT
21), the DR DOS 6.0 operating system returns 3.31. To some users
this seems as if DR DOS is trying to fool the application into
believing it is another OS. However, this is not the case. The
application needs to know that it should expect support for DOS
3.3-level calls and disk support for greater than 32 MB partitions
using the COMPAQ Extended Interrupt 25 and 26 convention. 

DR DOS must report 3.31 in order to give the application the
correct information it needs in order to work properly. Most DOS
applications use the 3.31 conventions mentioned above and therefore
work without any difficulty. This was one of the reasons Digital
Research decided to create DR DOS based on an existing DOS format
(3.31) rather than creating a new one (such as 6.0).

Usually, a DOS 3.3 driver works properly. If you have been running
previously with MS/PC-DOS 4.x however, the driver that you have
been using might be designed specifically for version 4.x. This
could also be true if the previous OS was MS-DOS 5. Contact the
manufacturer of the driver to see if they have any specific
configuration information or drivers for DOS 3.3x.

There are also some drivers that offer 3.3 disk support but not
3.31. The difference has to do with the capacity of the disk drive.
DOS 3.31 will support greater than 32 MB partitions while 3.3 only
supports a maximum of 32MB. If your driver does not work correctly
on large (>32MB) partitions contact the manufacturer and inquire if
they have 3.31 compatible drivers.

Some applications have been designed to go beyond these conventions
and actually attempt to directly manipulate DOS data structures or
replace sections of the operating system code with their own. These
applications depend on having intimate knowledge of each DOS
version they detect and have been written to react differently for
each of those versions. If an application uses this type of
technique, the manufacturer will have to design the application to
take the DR DOS 6.0 operating system into account as well. While DR
DOS does offer 3.31 support it's structures and code are very
different from COMPAQ 3.31. It is possible that the manufacturer is
aware of this and has already produced another version of your
application or driver that runs under the DR DOS 6.0 operating
system. 

Contact the manufacturer to see if there is any information about
upgrades or specific configuration steps for the DR DOS 6.0
operating system. If the manufacturer is interested in more
information about the DR DOS 6.0 operating system, they are welcome
to contact Novell directly at (800) NETWARE.