Reply 60 of 71, by darry
xcomcmdr wrote on 2020-06-17, 09:30:
All of that is true, except the part "Win9X runs under DOS". Win9X uses DOS as : a) a bootloader b) a compat layer (all of the a […]darry wrote on 2020-06-17, 07:53:
The version of MS-DOS that is provided with Windows 98 SE (95 and 98 FE too) , whatever Microsoft,you, me or anyone may choose t […]
The version of MS-DOS that is provided with Windows 98 SE (95 and 98 FE too) , whatever Microsoft,you, me or anyone may choose to call it,
a) can be run standalone (without loading the Windows kernel)
b) can be booted entirely from a floppy disk
c) supports all DOS APIs
d) allows direct access to BIOS function calls
e) allows direct hardware access
f) runs in real mode by default
g) can run DOS compatible memory managers
h) is compatible with all DOS extenders that can run under the previous standalone version of DOS (6.22)
i) Runs essentially all DOS compatible software that can run under the previous standalone version of DOS (6.22), the exception being certain low-level disk utilities (because of the addition of FAT32 and the support for drives larger than 8.4GB).
All of that is true, except the part "Win9X runs under DOS". Win9X uses DOS as :
a) a bootloader
b) a compat layer (all of the above is thanks to that)
But other than that, it's very much like in Windows 3.X but extended since then :
Upon boot, it takes reign of the machine (that's why sometimes you STILL have to use the real thing for some games, because Windows does a lot to 'hide' itself but it cannot be perfect) with its own pre-emptive kernel (pre-emptive for Win32, cooperative for Win16/DOS stuff) that runs in protected mode, its own flat memory model (bye bye conventional memory, high mem, xms/ems and stuff), along with its own set of drivers and a lot of (incompatible with DOS) Win32 apps that all use its new API.
So overall :
https://devblogs.microsoft.com/oldnewthing/20 … 224-00/?p=24063
I agree with point a) (I had oversimplified to the point of inaccuracy ) and with point b), expect that I believe that it is not quite accurate to say that "all of the above is thanks to that", as it implies that, in a way, DOS depends on Windows 9x and that we have it to thank for its (DOS) featureset (whereas DOS was obviously there first).
I think I understand that what you meant by it was that DOS would not be there in its current form in Windows 9x had Microsoft not chosen to use it as a compatibility layer but, even then, a way to run DOS programs natively would still have needed to exist. Maybe its just me gleaning meaning where there wasn't meant to be any .
I also agree with the rest of yout post .