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How to have permission to access ports?

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nobody:
I write a simple code to read a port with the in instruction but when i run the program the in al, dx create a segmentation fault.

I find that to use in or out instruction in linux i first need permission but i don't know how?

The code:

global _start

section .data

section .text

_start:

mov dx, 03f8h
in al, dx

xor ebx, ebx      ; send 0 as 'exit code'
mov eax, 1      ; terminate process
int 80h         ; execute the syscall

nobody:
I think you should use a1 (that's a one)  instead of al (that's an L).

Frank Kotler:
What effect do you get by replacing "al", a register name, with "a1", an undefined symbol??? Won't assemble for me. :(

Try sys_ioperm.

Best,
Frank

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