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- Path: sparky!uunet!sun-barr!decwrl!bu.edu!jade.tufts.edu!news.tufts.edu!news.tufts.edu!tguez
- From: tguez@jade.tufts.edu (Name)
- Newsgroups: comp.os.ms-windows.misc
- Subject: Re: Windows == OS
- Message-ID: <TGUEZ.92Aug26193535@jade.tufts.edu>
- Date: 26 Aug 92 23:45:42 GMT
- References: <714807912.2@ttlg.ttlg.UUCP>
- Sender: news@news.tufts.edu (USENET News System)
- Organization: Tufts University - Medford, MA
- Lines: 153
- In-Reply-To: Monroe.Thomas@ttlg.UUCP's message of 26 Aug 92 04:57:04 GMT
-
- > >virtualizes like an operating system virtualizes. Yet, this is all
- > >nothing more than a layer of primitives. You have to use window's
- > >primitives to fell this "virtualization" try accessing any of these
- > >things you mention directly and see how much of virtualization windows
- > >truely provides.
- >
- > Huh???? Do you know what you are talking about? Any "good" OS
- > always hides the hardware from the software developer. If you want to
- > access a hardware device, you have to do so through SYSTEM calls with
- > a well defined API. The OS then takes care of device contention,
- > allocation, etc... This is why DOS is *not* a good OS, because it
- > lets software developers manhandle the hardware without DOS's
- > knowledge. I think anyone would agree that Unix is a "good" OS. How
- > do you think that malloc is implemented? It eventually makes a system
- > call (through that system's API) requesting memory. The system then
- > returns with a pointer to that piece of memory.
- Read the response for Heath's post about the difference between
- Operating System API, and what windows offers.
-
- > And what do you think an OS is except a bunch of "primitives"?
- > How do
- Again the same response as the paragraph above, and there is a difference
- between UNIX layer's WHICH YOU CANT BREAK and windows layers WHICH ARE
- SOOOO FRAGILE as you said because it's DOS's fault. This is excellent;
- another argument that Windows DOES NOT TAKE over essential operating
- system responsibilities from DOS!
-
- > >> >touch it because now you have the malloc pointer. Yet a true
- > >> >operating system, which supports this feature, does not care that
- > >> >you have the actual pointer, it changes the base address of your
- > >> >pointer on the hardware level.
- > >> Actually, Win 3.1 changes the base address on the hardware
- > >> level. By abandoning real mode, Windows has gained greatly in
- > >> memory management abilities. Now, you can lock thatHGLOBAL
- > >> use the pointer throughout your App's life. When you quit, just
- > >> unlock it once. Windows will still be able to juggle your blocks,
- > >> it just doesn't have to have your cooperation to do it.
- >
- > >Once more the same old same old, use window's primitves and you get
- > >the abstraction, the point is that if windows was a real operating
- > >system I could use malloc and the operating system could still juggle
- > >with my memory blocks.
- >
- > Once more "the same old same old", every OS should provide this exact
- > amount of abstraction. With Windows you CAN just malloc, Windows
- > *will* "juggle" with your memory blocks. How else do you think
- > virtual memory is implemented?
- Execuse me!!!! Windows WILL NOT touch your malloc memory blocks,
- and it will sort of juggle with your memory only with near pointers and
- that is also only because you got the same DS value; that is it does
- not play with your memory blocks in relation to your malloc calls, it
- will move your WHOLE program by changing the base address. Compile
- in the compact or huge models where everything is far and windows will
- die a horrible death if it tried to play with it.
-
- The sort of virtual memory windows provide is a joke compared to
- UNIX's virtual memory (a real OS), where whole processes get swapped
- out, readable and writable memory is swapped out. Windows has a long
- way to go before real virtual memory support will appear. AGGGGAIN,
- windows could not do this because it's still a slave for DOS which
- is a sorry execuse for an operating system now days.
-
- > Your understanding of what an OS should be is terribly limited... you
- > seem to be using DOS as an example of what a true OS can do. Most
- > good DOS apps bypass DOS entirely when needing access to system
- > resources... DOS simply loads them into memory and executes them.
- > All "good" OS's NEVER, NEVER let application programs access the
- > hardware directly.
- I am sorry Sir, this group is not known for dog-fighting. If you want
- dog-fighting join some of the discussions in comp.os.windows.advocacy.
-
- WRONG! I don't use DOS as an example of what a true OS CAN do. I
- highlight things that an opearting system takes care of and show that
- windows is still a child to DOS; In that DOS is the operating system
- opearting the PC, when you use windows. I have never presented DOS as
- THE operating system.
- >
- > >WindowsNT is another issue (another operating system not a GUI),and
- > >Windows 4.0 is another story, and hay, I just read a post that says
- > >that DOS 6.0 has a few things changed to make it ready for Windows
- > >4.0, and among other things, make some changes to DOS 6.0 so that
- > >windows 4.0 could become preemtive. Hence, Windows does not solely
- > >use DOS as a system device driver after all.
- >
- > Again, it is woefully apparent that you don't grasp what operating
- > systems are all about. That's OK... lots of people use OS's without
- > understanding them. Just because I use a car doesn't mean that I'm an
- > expert on internal combustion engines.
- English is not my native tongue, and I have been using it on
- day-to-day basis for only two years. Therefore, I may use the wrong
- words or I may grammatically structure a sentense that would be more
- transparent otherwise. You should, therefore, pay much more attention to
- the essence of the argument than it's surface appearance.
-
- Let me help you understand that paragraph: without any knowledge of
- how Windows or DOS are actually written (no source code) one must
- improvise. Someone said that Windows 4.0 is going to introduce
- preemtive multi-tasking. Another post said that, among other things,
- DOS 6.0 is a mutli-tasking DOS (the exact meaning of which was not
- clear). Yet another, earlier, post said that MS is preparing DOS 6.0
- for the upcoming WINDOWS 4.0. If you sit back now, and digest these
- three pieces of information you will see that windows cannot alone
- handle preemtive mutli-tasking (for window's apps), it needs some help
- from DOS, hence windows is NOT an operating system. Now, again try to
- understand what I write. I do not mean that multi-tasking equals an
- opearting system. It should be clear to you that if you try to
- introduce multi-tasking to a non-multi-tasking environment and you
- cannot do it without making the non-mutli-tasking environment
- multi-tasking, you are seriously dependent on this non-multi-tasking
- environment, most likely to an extent of a master-slave
- relationship,i.e., Opearting System-Application.
-
- If you follow this discussion, as it seems you have, you will
- encounter a post in which someone said that DOS is sort of a
- "device-driver" for windows. So, when I write, "Hence, windows does
- not use DOS as a device-driver after all." I refer back to that to
- show that the concept of is not true, and in this particular example,
- DOS is more than a device-driver for windows.
-
- > >> So what if it is? That is a lot like what UNIX does, too.
- > >> Windows also provides for interprocess communication, device
- > >> sharing, serialization of input, virtualization of all hardware,
- > >> file locking and sharing, true preemptive multitasking with DOS
- > >> boxes in enhanced mode.
- > >Noooo, unix plays with the stack and does context switches and all
- > >sorts of things. You see if the loop outlined above is a good guess
- > >of what's happending (again, never seen the source code), then the
- > >function WinMain uses the same stack as the calling program (simple
- > >function call). Hence, in order to introduce preemptive multi-tasking
- > >there should be some arrangement to make a copy of the stack, and hold
- > >a few stocks in memory and switch between them and take care of PCLBs
- > >and all sorts of things that windows does for DOS apps but not for
- > >windows apps.
- >
- >
- > Huh??? You've never seen the source code, but you know this? How an
- > OS multitasks has nothing to do with anything but multitasking.
- You don't have to see the number 123456! to know it exists. If you
- read carefully the text-books describing the functionally of windows,
- and you know the general mechanics (implementation) of these concepts
- you don't have to see the code. If I tell you that FORTRAN has no
- stack, you don't need to be told that you cannot do recursion, and if
- I tell you that PROLOG is a declarative language, you would be stupid
- trying to find a for statement in a prolog manual.
-
- > I suggest heading down to the local library and grabbing a book on
- > operating systems. Read it, and then come back and tell us this all
- > over again.
- Although you are very interested in my background, I will have to
- disappoint because that does not make an argument valid, sound or
- convincing-- I will not comment on that for now.
-
- Tomer
-