ASM Community

ok, it's vbasic again, but i really mean it. the following program tries to load "msvbvm60.dll" (should work), get the address for "rtcInputBox" (should work too), and then call that function with parameters. !but: when i call it, the programs exits with a page fault. i guess this is due to false parameters passing. does anybody know how to solve this problem? is there something with the number of parameters or the type of them?
PLEASE help!!!!! i want to get it.

.386

.model  flat, stdcall

option  casemap: none



include \masm32\include\windows.inc

include \masm32\include\kernel32.inc

include \masm32\include\user32.inc

includelib  \masm32\lib\kernel32.lib

includelib  \masm32\lib\user32.lib



.data

    hMsg    HINSTANCE   0           ; contains handle of library

    iProc   dd  0                   ; address of function

    ;

    szDll   db  "msvbvm60", 0       ; name of library

    szProc  db  "rtcMsgBox", 0      ; name of function

    szTText db  "Text", 0           ; message prompt

    szTCapt db  "Caption", 0        ; message caption

    ;



.code



 main:



    push    offset szDll            ;

    call    LoadLibrary             ; try to load "MSVBVM60.DLL"

    cmp     eax, 0                  ;

    jz      @error                  ; if eax==0 -> fail

    mov     hMsg, eax               ; else store handle



    push    offset szProc           ; function

    push    hMsg                    ; handle to library

    call    GetProcAddress          ; get address

    cmp     eax, 0                  ;

    jz      @error                  ; if eax==0 -> fail

    mov     iProc, eax              ; store address



    push    0                       ; msg-type

    push    offset szTCapt          ; msg-caption

    push    offset szTText          ; msg-prompt

    push    0                       ; owner handle

    call    MessageBoxA             ; success confirmation thru user32.dll



;; ---------------------------------------------------

;; the following piece of code causes an error and brings

;; up the debug window: page fault in msvbvm60.dll

;;

    push    offset szTCapt          ; message caption

    push    48                      ; message type

    push    offset szTText          ; message prompt

    call    [iProc]                 ; call rtcMsgBox

;;

;; ---------------------------------------------------



    push    hMsg                    ;

    call    FreeLibrary             ; free handle to "MSVBVM60.DLL"

    

    jmp     @end



  @error:

    jmp     @end



  @end:

    push    0

    call    ExitProcess             ; exit program



 end main

name them!!! for god's sake .... i don't need to be told there are errors -- tell me where they are!

vb6 runtime dlls do export just like any other dll. I once saw a C program that was written almost entirely against the vbm6 dll to handle it's memory allocation and pointers and some of it's internal COM memory as well. not a very easy to understand program but it was internesting. I've used a utility to intercept thec ompile process for VB only to see it actually uses the C3 and ML compiler that exports to assembly and compiled by masm. The c3 compiler with the /basic command line option. However, this isn't a feat I'd have interst in to use the vbm6.dll in my own applications.


Thanks,
_Shawn

Afternoon, ploptor.

Sorry. It seems this messageboard has decided to become "elitist", and members would rather ridicule and insult other members' comments, rather than actually help someone (yourself) learn to use win32 assembly programming.

Cheers,
Scronty

Im making a wild guess here but the VB function might be expecting unicode strings?


Bazik - I see more errors than sense in this statement. In fact I see very few errors in the code.

@_Shawn:


do you still have that program? or could you tell me where i can find it?

Thats why I posted my reply above :)

I admit I discovered the same as Scronty which was not a real error :)
Anyway, IMHO its senseless to use MSVBVM60.dll from assembly :)

bazik, as I have already told you: you should be more reserved in your responses. If you cant help you should consider to resign as mod.

What does the VB Library provide that this community can't?