[comp.os.os2.programmer] OS/2 DOS compatible box

william@ashtate (William Wong) (09/20/90)

I have a question concerning the OS/2 DOS compatible box.

How does a DOS program detect that it's running in the OS/2 DOS compatible
box?

I have tried using the INT 21 service 30h to get the DOS version.  It
returns AL=10, AH=10 when run under OS/2 version 1.10.  Now the minor
version in AH seems correct, but I am not so sure about the major version
number in AL.  Does OS/2 DOS compatible box always return its version
number times 10 to distinguish itself from the regular DOS?

William

prk@planet.bt.co.uk (Peter Knight) (09/20/90)

william@ashtate (William Wong) writes:



>I have a question concerning the OS/2 DOS compatible box.

>How does a DOS program detect that it's running in the OS/2 DOS compatible
>box?

>I have tried using the INT 21 service 30h to get the DOS version.  It
>returns AL=10, AH=10 when run under OS/2 version 1.10.  Now the minor
>version in AH seems correct, but I am not so sure about the major version
>number in AL.  Does OS/2 DOS compatible box always return its version
>number times 10 to distinguish itself from the regular DOS?

>William
Yes.
Peter Knight
BT Research

#inlcude <std.disclaimer>

cowan@marob.masa.com (John Cowan) (09/20/90)

In article <1251@ashton.UUCP> william@ashton.UUCP (William Wong) writes:
>Does OS/2 DOS compatible box always return its version
>number times 10 to distinguish itself from the regular DOS?

I don't think it's been defined whether it's a version number times 10
or plus 9, but at any rate, if the version number >=10, you can assume
the compatibility box.
-- 
cowan@marob.masa.com			(aka ...!hombre!marob!cowan)
			e'osai ko sarji la lojban

lsalomo@donald.uucp (Lawrence W Salomon) (09/27/90)

OS/2 returns the major version number as 10+version number of OS/2.
Q