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Re: Can I do this?

On 19 Nov 97 at 13:20, the Illustrious John Wizorek wrote:

> I am searching for a tool that will allow me (with Win95 of NT) to
> "mount" a tape drive (Sony SDT9000) and be able to extraxt "TAR" files
> from tapes we recieve.  Will this work???

	Not without the Sony supplied h/w driver for the tape machine you are
referencing being pre-installed on your NT machine.  This appears to be a
limitation of  the NT OS that has been re-inforced by the revised
dependance of the NT OS on the Hardware Abstraction Layer (HAL).

	If you're running Alpha or some other Unix based machine, you could (I 
assume based on my use of Unix and/or Linux) simply boot directly to Unix 
in order to handle such mountings and thereby bypass any limitations that 
NT places on any associated hardware.

	Apparently Unix  and any MS-DOS prior to Win95/98, don't seem to have any
problem when directly calling things like tape drives; whereas NT and most 
of the recent MS OS platforms have a great deal of problems "mounting" 
things from a qualifed userid level.

	As an example, I can "mount" my external tape drive under the MS-DOS 
side of this box (pre Win95) using interrupt calls to the OS itself 
without the need to go through any sort of hardware layer to get there as 
long as the code for accessing the tape drives' h/w registers is 
available.  It's not necessarily a Unix "mount" but it functions in much 
the same way.

	Back to Win95/98...Win95/98 still doesn't really have any system security 
at the hardware level.  One of the things admired by those who do purchase
NT (for enterprise applications only) is the fact that only the HAL can
interact/interface with the h/w.  Nothing else can.  It is the lack of 
this ability under Win95/98 that allows MS to generate a new DirectX 
package every few months for Win95/98 based machines.

	NT, on the other hand, requires that the HAL be updated to facilitate any 
revised hardware calling functions that might be included with the latest 
and greatest DX SDK.  If this is not accomplished, then, under NT, the 
latest and greatest DX SDK simply will not work.

	I am sure MS is proud of this fact, and well they should be when it comes
to keeping the actual hardware level secure from unwanted virusi or
end-user tampering when it comes to enterprise operations...I think that
in MS terms, the NT buzz phrases,  "Zero Administration" or "Reducing 
Total Cost of Ownership" (TCO) are applicable here.

	Of course, the disadvantage, in both cases, is that no end-user (as 
opposed to a device driver programmer) can directly access things like 
device registers without the *ahem* "appropriate" h/w calls (call it 
authorization) as defined by the HAL or Hardware Abstraction Layer of NT 
4.0 or later.  These HAL calls are dependent on the h/w driver in 
question...for the current tape reference case (SDT9000) this, I think, 
would definitely apply.

	Here is the scenario as I see it...please, anyone, feel free to expand on 
this...I do not consider myself an expert by any means when it comes to 
Win32 based operations.  Systems are a different story.

	Under Win95, the programmer can directly access any and all hardware
without any sort of special case scenarios outside of those required to
understand (programmatically speaking) the hardware in question (things 
such as h/w specs available with a Video Card).  Under NT this is not the 

	Any and all access to hardware registers under NT 4+ is restricted to the 
HAL itself and must be passed through the HAL before that specific 
h/w access can be accomplished.

	Now, and as mentioned earlier, if you have the NT specific h/w drivers 
for the SDT9000 necessary for NT 4.0+ there would be no problem...if you 
do not, then I am afraid you are out of luck unless you want to enter the 
rarified world of NT Hardware Device Driver programming.  I hear that the 
pay is very good...


		Paul G.

Chronicles of Aurum: Book I
      A Journey Into the Fantastic
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