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Index > Windows > Push address for scanf

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zeritonik



Joined: 10 Jul 2022
Posts: 1
zeritonik
I want to input array using scanf, but I don't know the proper way to do push address of element.
Code:
LENGTH = 4
ELEMENT = 2
arr rw LENGTH
scanf_si db "%hi", 0

mov ecx, LENGTH
mov di, 0
input_arr:
push arr + di ; invalid expression
push scanf_si
call [scanf]
add di, ELEMENT
loop input_arr
    

If I store array address in register and push it, code will work fine, but I know, that address can be calculated this way in some situations. I want to know if I can push address without using registers[/b]
Post 10 Jul 2022, 16:26
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 18846
Location: In your JS exploiting you and your system
revolution
Code:
arr rb LENGTH ; you probably want to reserve bytes, not words
push arr ; use the address directly    
Post 10 Jul 2022, 18:23
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AsmGuru62



Joined: 28 Jan 2004
Posts: 1464
Location: Toronto, Canada
AsmGuru62
Also, call to [scanf] will most likely destroy ECX register and LOOP instruction will continue for more times, or less, than needed.
Post 10 Jul 2022, 21:19
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 18846
Location: In your JS exploiting you and your system
revolution
I missed that you are using di as an index. You can do this:
Code:
mov di, arr
push di
;....
add di, ELEMENT
;...    
Post 10 Jul 2022, 21:59
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