M. R. Brown
Tue Nov 30 23:39:00 GMT 1999

NT by its nature doesn't allow direct hardware access to _ANY_ user
program, only device drivers are allowed to get low-level with your
hardware, and writing one is not a walk in the park :)  You can search the
net for a generic NT device driver that allows arbitrary I/O port access
using IOCTLs, or you can roll your own.  Even the practice of writing
directly to I/O ports is depreciated under Windows 9x, as 9x "attempts" to
do some hardware management.  To my knowledge, cygwin doesn't support any
functions regarding ioport access (think about it, does VC++ have any
methods of rw I/O ports?).


On Wed, 17 Nov 1999, Philippe PUJAS wrote:

> I want to manage directly ioport from inp/outp (inb,outb) commands under
> Cygwin20.1/NT4.
> 1st These instructions don't exist on Cygwin20.1
> 2nd I try the assembler routines from the FAQ and I get the following
> message : handle_exceptions: Exception STATUS_PRIVILEGED_INSTRUCTION
> Thank you for your help.

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