Linking Source with a API-Procedure

format MS COFF extrn _Str extrn '__imp__ExitProcess@4' As ExitProcess:dword extrn '__imp__MessageBoxA@16' as MessageBox:dword section '.text' code readable executable public _4compiler _4compiler: push 5 call _Str mov [var],eax push 0 push _S4 push [var] push 0 call [MessageBox] ;______________________________ push 0 call [ExitProcess] ret section '.data' Data readable writeable var dd ? _S4 db "Test",0

format MS COFF extrn '__imp__wsprintfA@8' as Convert:dword section '.text' code readable writeable shareable public _Str _Str: pop edx pop eax push edx push eax push _S3 push buffer call [Convert] mov eax,[buffer] ;<- here's the error to my mind ret section '.data' Data readable writeable _S3 db "%d",0 buffer dd ?

ronnie wrote:

HI,
I wanted to link this source:

Code:

format MS COFF

extrn _Str
extrn '__imp__ExitProcess@4' As ExitProcess:dword
extrn '__imp__MessageBoxA@16' as MessageBox:dword

section '.text' code readable executable

public _4compiler

_4compiler:

        push 5
        call _Str
        
        mov [var],eax
        push 0
        push _S4
        push [var]
        push 0
        call [MessageBox]

;______________________________
        push 0
        call [ExitProcess]
        
        ret


section '.data' Data readable writeable
var dd ?
_S4       db     "Test",0

with this one:

Code:

format MS COFF

extrn '__imp__wsprintfA@8' as Convert:dword

section '.text' code readable writeable shareable

public _Str
_Str:

pop edx
pop eax
push edx

push eax
push _S3
push buffer
call [Convert]
mov eax,[buffer]        ;<- here's the error to my mind
ret 

section '.data' Data readable writeable
_S3       db     "%d",0
buffer       dd ?

I want to know how to transport register between two compiled obj ?

What do you mean by transport register?

You probably want to link these together, if you are using MS Link or Polink, a linker response file looks something like this:

Code:

-heap:0xF4240,0xF4240
-stack:0xF4240,0xF4240
-base:0x4000000
-entry:_4Compiler
-section:.data,RW
-section:.text,ER
-machine:ix86
-subsystem:windows
-nologo
-out:demo.exe
kernel32.lib
user32.lib
str.obj
comp.obj

This is assuming your files are called "str.asm" and "comp.asm" change them as necessary.
I see you also use one of the C libraries. I don't know what its called, you'll have to link in that library too.
Also, I believe the C calling convention is different. You have to balance the stack by adding the byte value of all the pushed parameters to ESP.

To link, assuming the linker response file is called "comp.link"

> polink @comp.link

Quote:

It would be helpfull if you give me links and tutorials about writing and calling procedures in assembly, too

Try AoA:
www.artofassembly.com

The book covers everything from low level aspects to high level displays and frames, along with many different calling conventions.