操作后NASM INTEGER INPUT和PRINTING INTEGER

Question

我是nasm的新手，我正在尝试在nasm中执行以下操作，我正在使用mac osx。无论如何，只需指导我如何从控制台读取整数

.data
_num word 0
_sum    word 0
_msg1   byte "Enter a number: ", 0
_msg2   byte "The sum is: ", 0

.code
main proc

mov edx, offset _msg1
call writestring
call readint
mov [_num], eax
call writestring
call readint

add eax, [_num]
mov [_sum], eax

call writestring
call readint

sub [_sum], eax
mov eax, [_sum]

call writeint

exit

main endp
end main