suggest to provide a 2nd virtual at that holds real address.

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vbVeryBeginner

Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia

vbVeryBeginner 21 Mar 2006, 06:45

Code:

struct struct_fruit
        price   dd 1
        type    dd 2
        name    dd 3
        unit    dd 4
ends

mov  edx,fruit
virtual at edx
        .fr     struct_fruit
end virtual
mov  eax,[.fr.price]
mov  ecx,[.fr.unit]
invoke stockcontroldept,a,b,[.fr.unit]
invoke marketingcontrol,a,[.fr.price] ; the .fr.price would fails coz let say, stockcontrol already modify the EDX values

i would suggest maybe fasm could provides 2nd version virtual that holds real address instead of offset, so after the virtual at edx, we could call any invoke (which might modify edx values) but we need to access to [.fr.price] after the invoke, current way is to push the edx and pop them out.

21 Mar 2006, 06:45

vbVeryBeginner

Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia

vbVeryBeginner 21 Mar 2006, 06:52

the problem would still be there if we are going to use fruit as an array Sad

perhaps anyone could guide me a little bit how to solve issue like above?

21 Mar 2006, 06:52

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8146
Location: Kraków, Poland

Tomasz Grysztar 21 Mar 2006, 07:52

Well, if fruit is just some absolute address, you can do something like

Code:

virtual at fruit
 .fr struct_fruit
end virtual

But if it is an address you can get only into a register at the run-time, you have to preserve that register to keep it.

21 Mar 2006, 07:52

vbVeryBeginner

Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia

vbVeryBeginner 21 Mar 2006, 16:38

yip yip,
thanks.

21 Mar 2006, 16:38

vbVeryBeginner

Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia

vbVeryBeginner 10 Apr 2006, 19:27

sigh,
i spend hours today to find why i coudln't get a value from a struct...
coz i didn't aware that after i
virtual at edx
and i do some invoke
and i reffer to my virtual struct.. (off course, it would fail like i mentioned above).

stupid me.

10 Apr 2006, 19:27

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