A 16-bit applicaiton with ASM code which access physical address

NTFSD
1

Hi All,

I have a 16-bit application, which is developed using Turbo C, which
contains the assembly code to read the physical address is working fine on
Windows 2000.

But I thought that there will be restriction for the applications (running
in user mode) accessing the physical address. How is this application
working. When application developed through turbo C is running why cannot
applications developed using MSDS use such kind of code and run?

Any information is helpful.

Thanks,
Kedar.

2

Hi Kedar,

What makes you think it is reading the physical memory?
The 16 bit Application would be running in an emulated mode.
It, I believe, is reading its virtual address space.

A windows application can read the physical memory by using
the object “\Device\PhysicalMemory”
http://www.sysinternals.com/ntw2k/info/tips.shtml#kmem

Regards,
Manoj

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com]On Behalf Of Kedar
Sent: Thursday, May 20, 2004 12:59 PM
To: Windows File Systems Devs Interest List
Subject: [ntfsd] A 16-bit applicaiton with ASM code which access
physical address

Hi All,

I have a 16-bit application, which is developed using Turbo C, which
contains the assembly code to read the physical address is working fine on
Windows 2000.

But I thought that there will be restriction for the applications (running
in user mode) accessing the physical address. How is this application
working. When application developed through turbo C is running why cannot
applications developed using MSDS use such kind of code and run?

Any information is helpful.

Thanks,
Kedar.