Re: Newbie Question About Device Drivers

From: Don Burn (burn_at_stopspam.acm.org)
Date: 08/02/04 

Date: Mon, 2 Aug 2004 09:32:05 -0400

In Windows NT/2000/XP/2003 you cannot access devices from a user space
program. Additionally, there are some capabilities such as system wide
monitoring of filesystem or network activities that need to be done in the
kernel.

Now the challenge is that the kernel is its own environment, with its own
API's and requirements. Additionally, in the kernel you have access to the
whole system space, so a mistake is likely to create a crash. So in general
if you can achieve what you want in user space, it is probably better to do
so. In fact Microsoft keeps talking about the possibility of some device
drivers (such as slow USB devices) being supported in user space in the
future.

Overall there are a lot of differences in the kernel and user programming,
give the group an idea of what you are thinking about and we can probably
give you guidance. 

-- 
Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting
Remove StopSpam from the email to reply
"TerryW @vbssys.com>" <prog<NOSPAM> wrote in message
news:nsesg0d47ajr92vmhtegqbv9isp3fmkn54@4ax.com...
> What is the difference between device drivers and low level C++ or C
> code?  What are the Pros/Cons of either?
>
> TIA
>
> Terry W
>

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