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MAD_DËMON



Joined: 03 Mar 2006
Posts: 23
MAD_DËMON
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plz how can i calculate the size of any string? i need it to work with the Write String func in the BIOS INT 10h

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Post 04 May 2006, 23:38
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LocoDelAssembly
Your code has a bug


Joined: 06 May 2005
Posts: 4633
Location: Argentina
LocoDelAssembly
place the following code before any string definition:
Code:
struc db [chars]
{ 
common 
    . db chars
    .size = $ - .
}    


Then you can use it this way: mov cx, PideNumDIgits.size

[edit]I see a bug in your code, you must place the the function number in AH, not AL, so use "mov ax, $1300" or "mov ah, $13". Also check http://www.ctyme.com/intr/rb-0210.htm to see what you prefer in AL, maybe you want to use "mov ax, $1301"[edit]
Post 04 May 2006, 23:52
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saigon



Joined: 29 May 2006
Posts: 62
saigon
@locodelassembly: Is there any other way?
I thought something like this, but it doesn't work:

mov cx, $-chars

Can you help me get that to work? Thanks!

EDIT: Ofcourse it doesn't work, because $ means "here", so I can't do that..
Post 12 Jun 2006, 19:01
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LocoDelAssembly
Your code has a bug


Joined: 06 May 2005
Posts: 4633
Location: Argentina
LocoDelAssembly
Here an example for DOS
Code:
struc db [chars]
{  
common  
    . db chars 
    .size = $ - . 
}

struc String [chars] ; As Turbo Pascal
{
common
  .size db 0
  .chars db chars
  store $ - .chars at .size
}
STDOUT equ 1

org 100h

mov ah, $40
mov bx, STDOUT
mov cx, message.size
mov dx, message
int $21

mov ah, $40
mov bx, STDOUT
mov cl, [pascalMessage.size]
mov dx, pascalMessage.chars
int $21

xor ax, ax
int $16

int $20

message db "Hello World!!", 13, 10

pascalMessage String "And now a Pascal hello world!!", 13, 10    


You can see a new Pascal-style string. Why do you need a different way?

Regards

PS: The db struc in my source is the same that the one explained in the FASM's manual, I think

[edit]Changed "STDOUT equ 2" 2 to "STDOUT equ 1". 2 is STDERR...[/edit]


Last edited by LocoDelAssembly on 12 Jun 2006, 20:53; edited 1 time in total
Post 12 Jun 2006, 19:56
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saigon



Joined: 29 May 2006
Posts: 62
saigon
Nice example!
I wanted to have the size stored only for one string instead for all of them.
Post 12 Jun 2006, 20:20
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RedGhost



Joined: 18 May 2005
Posts: 443
Location: BC, Canada
RedGhost
saigon wrote:
Nice example!
I wanted to have the size stored only for one string instead for all of them.


Code:
name db 'xxx', 0
name.size = $-name
    

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Post 16 Jun 2006, 08:47
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vbVeryBeginner



Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia
vbVeryBeginner
[unrelated]
if you guys like the font MAD_DËMON used, check here
http://www.dafont.com/font.php?file=bitstream_vera_mono

i just knew this font from MAD_DËMON through pm, thanks!
Post 16 Jun 2006, 10:34
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