Could someone please explain to me what giveio.sys is supposed to do? I am currently writing an application in Visual C++, and am adapting some other code for use in this application. The old code is supposed to use giveio.sys and is malfunctioning, but I don't understand enough about giveio.sys to fix it. Please help! Thanks so much!

Okay As you know NT does not allow applications to access hardware directly So what an app does is ask NT to access (arbitrate) harware and this is why NT is more stable than Dos based OSes like W95/98 This is done thru ports NT has a default list of I/O port addresses that are allowed to be used by apps. Now you are writing an app but you want to access hardware, normally you would have to write a driver for that hardware but you just don't have the knowledge or time. This is were it would be nice if our app could access the hardware directly This can be done by changing the default permission list to access I/O port addresses. Because this is not allowed in NT ( user mode) there has been developed a driver called giveio.sys to work around this problem SO what you are doing is more or less fu..... around with NT stability ;-) In fact you are using some undocumented kernel calls to fool around.