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Index > Macroinstructions > Get variable's raw offset

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booze



Joined: 24 Jul 2013
Posts: 2
booze
Hello,

is it possible in FASM get raw offset of a variable? I mean offset from the beginning of the physical file.

For example, I have a variable:
Code:
section '.data' data readable writeable
    var dd 0x00000001
    


If i write
Code:
section '.data' data readable writeable
    var dd 0x00000001
    var_offset dd var
    

var_offset will contain the VA of the var.

Also I can write
Code:
section '.data' data readable writeable
    var dd 0x00000001
    var_offset dd var - $$
    

Here var_offset will contain raw offset from the beginning of '.data' section. To get 'var' raw offset, I need to get '.data' PointerToRawData. How can I get it?

Thank you in advance, and excuse me my English.
Post 24 Jul 2013, 18:35
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l_inc



Joined: 23 Oct 2009
Posts: 881
l_inc
booze
Unfortunately, not possible. You can neither find the raw size of the header nor raw sizes of sections (because of possible uninitialized data at the end of sections).

I never needed this, but it still could be a nice feature to have. Like raw operator analogous to the rva operator.

_________________
Faith is a superposition of knowledge and fallacy
Post 24 Jul 2013, 19:29
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booze



Joined: 24 Jul 2013
Posts: 2
booze
l_inc
Thank you. Probably there is only one solution - patch the binary after assembling.
Post 25 Jul 2013, 07:13
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fasmnewbie



Joined: 01 Mar 2011
Posts: 553
fasmnewbie
I don't know what you meant by 'raw' offset but If you meant the starting address of the '.data' section then this is the way I always use.

section '.data' data readable writable
@myoffset:
;data declarations

mov eax, @myoffset
Post 30 Jul 2013, 20:45
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