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jacko221



Joined: 12 Nov 2005
Posts: 22
jacko221
Is there anyway to clear a string/buffer in my code?
For example if i define:
buffer db ?
and it gets filled with data in my code... but later i want to clear it.
How would i go about doing such a thing?
All help is appreciated Smile
Thanks, Jack
Post 14 Oct 2006, 14:15
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17279
Location: In your JS exploiting you and your system
revolution
jacko221 wrote:
i want to clear it.
How would i go about doing such a thing?
like this:
Code:
mov [buffer],0    
But, are you sure you want a string buffer to be one byte long? Perhaps you want:
Code:
buffer rb 1024    
Then you can use something like this to clear it:
Code:
mov edi,buffer
mov ecx,1024/4
xor eax,eax
rep stosd    


Last edited by revolution on 14 Oct 2006, 14:54; edited 1 time in total
Post 14 Oct 2006, 14:39
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vid
Verbosity in development


Joined: 05 Sep 2003
Posts: 7105
Location: Slovakia
vid
if you mean filling with zeroes, it's:
Code:
cld
mov edi, buffer
mov ecx, size_of_buffer
mov al, 0
rep stosb    
Post 14 Oct 2006, 14:45
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smiddy



Joined: 31 Oct 2004
Posts: 559
smiddy
Both vid and revolution are correct, however I will point out, you need to ensure that ES and DS are in the same segment/selector as the buffer, otherwise you'll put them zeros into space you may not want them to go.
Post 14 Oct 2006, 17:09
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jacko221



Joined: 12 Nov 2005
Posts: 22
jacko221
thanks for all your help Very Happy
Post 15 Oct 2006, 03:32
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