On Fri, 18 Jan 2002 18:20:18 Rahul Saxena wrote:

hi everyone,

I was tryign to read/write bits to 0x378 I/O port, using the ioperm() system call. But this allows only the root to access.

I think you should explore better ways than directly allowing the users to access the port, like writing a device driver module. Not that I've ever done that, but I have this wariness for allowing users to access the hardware directly. That was the DOS way of doing it, right?

HOw do normal users access the port? i did read about SETUID(), but i dont really understand how it works for me ??

# chown root:root <filename> # chmod a+sx <filename>

does anyone have any pointers on this ??

Also i am trying to uderstand how ot access using read and write. for that i would need to add the user as part of the group, which can access /dev/port.

How do i add myself to the group? i guess.. in that case i wont be in my original group.

I really think it would be best if you do it the accepted way (I consiously avoided the word "right" :-). Normal users aren't supposed to be accessing I/O ports directly. Try going thru _Linux Device Drivers_ by O'Rilley Publications for enlightenment.

Thanks for reading

-rahul

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