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I'm having problems with data declarations in modules:

.386
.model flat, stdcall  ; 32 bit memory model
option casemap :none  ; case sensitive
include windows.inc
include user32.inc

.data
szText db "Module 4",0
szCaption db "Caption 4",0


.code

Module4 proc hWin:HWND
LOCAL hList:dword
invoke GetDlgItem,hWin,1005 ;Windows API result gets stored in eax
mov hList,eax
invoke SendMessage,hList,LB_ADDSTRING,0,offset szText
        invoke SendMessage,hList,LB_ADDSTRING,0,offset lpstMenu ;lpstMenu defined in module.inc

ret

Module4 endp

end


;lpstMenu is declared global and should be visible in all modules? This will give me the following compile error:
Assembling: Mod\Module4.asm
Mod\Module4.asm(21) : error A2006: undefined symbol : lpstMenu
if I try externdef szText or extern szText
I get:
Assembling: Mod\Module4.asm
Mod\Module4.asm(8) : error A2008: syntax error : in directive

Also how to make this visible to all modules?
IDM_File      equ 1001 I thought this was a global constant??

What is the proper way to expose global data to other modules?

hi

I understand your sourcecode not and
your correct problem send your sourcecode

i could probely could help you

lpstMenu must declarations in your modules
if that helps you only times

greets ragdog

Here is my code

I'm trying to load my menu from Module4 and display menu string to the list box.
I have commented out the last 2 instructions, so that the program runs.

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Klod,

Have a look at the PUBLIC operator in MASM where you declare the data and EXTERNDEF in the module where you use the data. (Spelling corrected on EXTERNDEF).

I hope it help you


greets
ragdog

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Thanks to you all
The PUBLIC and EXTERNDEF do the job, but its not exactly what I was after.
After playing around for a bit, it became obvious to me, that the problem I try to solve may be one of scope and of style.
Let me try to explain:
a proc may need data that is global and I would like to keep the declaration in the proc (readability) like this:

EditBoxProc proc

GLOBAL arrEdit dd 6 dup(0)   ;global array holding the handles of the edit boxes
GLOBAL rc DD 10,0,90,18,10,23,90,18,10,46,90,18,10,69,90,18,10,93,90,18,10,116,90,18,10,139,90,18    ;coordinates of editboxes

push EBX
push ESI
push EDI   
ASSUME eax:PTR RECT
mov esi, offset rc        ; base address of tbl rc

    mov ebx,0
    top:
       cmp ebx,6
      je lout
      mov eax, esi   ;offset rc
      invoke CreateWindowEx,NULL,SADD("EDIT"),SADD("Test "),\
      WS_VISIBLE OR WS_CHILD,[eax].left,[eax].top,[eax].right,\
      [eax].bottom,hWnd,NULL,hInstance,NULL
      mov DWORD PTR arrEdit[ebx],eax
      add esi,16
      inc ebx
      jmp top
   lout:
   pop ebx   

      assume eax:nothing
     ;invoke SetFocus, arrEdit(3)    ;set focus if needed
pop EDI
pop ESI
pop EBX      
ret
EditBoxProc endp

This works well if called from within the same module. But if I make call from another module, I get a link error arrEdit not defined. I conclude that arrEdit is global to this module but not to the entire program.
I could call the proc by passing the parameters but this would mean I would have to create stackframes for each call.
Is there a way around this delemma?

hi Klod

here is your souce

hav a nice day :bg

greets
ragdog

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Thanks ragdog  for your help.
Your code is were I started from, with the exeption that I used the GLOBAL macro instead of the better declaration for the arrays in .data.
The problem I have tryed to solve is that if I have procs that do not create a stack frame, I can't access global data directly, if hInstance is declared in module.inc and i try to access it from module1.asm then I get a compile error:
Mod\Module1.asm(19) : error A2006: undefined symbol : hInstance.
The Public and EXTERN combination that Hutch suggested works, but it defeats my initial idea to declare global data in the module it is first used (my style). Also much more typing.... more errors...
I have found 2 working solutions:
1. to create stack frames and pass the parameters via invoke hInstance, param2 syntax
2. to keep all functions that need access to global data in the same module the global data was declared.
maybe there are more solutions ?

Quote from: Klod on February 25, 2007, 12:21:59 AM
I have found 2 working solutions:
1. to create stack frames and pass the parameters via invoke hInstance, param2 syntax
2. to keep all functions that need access to global data in the same module the global data was declared.
maybe there are more solutions ?

Yes. Declare the data in a .data section in one module. Then in every module (including the one you declared the data in), put EXTERNDEF myData:DWORD (or whatever the names and types are). This is the idea method and is incredibly easy if you create a Globals.inc and put all the EXTERNDEFs in there.

Cheers,

Zooba :U