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So, i have this dll file called dllFile.dll. Inside this dll file there is this function called dllFile() which i will call from my main program.

So i first extract the function into a library file dllFile.lib using the linker options:


And the contents of the dllFile.def definition file is:

LIBRARY dllFile.dll
EXPORTS dllFile

Now that i have my library file i just link it with my main program and it links successfully but when i try to open the program it crashes giving me an error.

The dll file happens to be made by me so i have the source code. If i directly create a library from the source code instead extracting it from the dll and then compile it back with my main program it works.


The problem is that this dll file happens to be made by me. So, if i were to have a dll file and only have it's function names in a definition file (.def) then i wont be able to make it work properly because it crashes. So, i am wondering what i am doing wrong.

(dllFile.asm)

.586
.model flat, c

includelib kernel32.lib

.code
public dllFile
dllFile proc,
	lpBuffer:dword,
	nNumberOfCharsToWrite:dword,
	lpNumberOfCharsWritten:dword
	
	STD_OUTPUT_HANDLE equ -11
	extrn	GetStdHandle@4:near
	push	STD_OUTPUT_HANDLE
	call	GetStdHandle@4
	
	extrn	WriteFile@20:near
	push	0
	push	lpNumberOfCharsWritten
	push	nNumberOfCharsToWrite
	push	lpBuffer
	push	eax
	call	WriteFile@20
	
	extrn	ExitProcess@4:near
	push	0
	call	ExitProcess@4
dllFile endp
end

(main.asm)

.586
.model flat

includelib dllFile.lib

.data
bytesWritten dword ?
printStr byte "This better work!",0Ah,0
printStrSize equ lengthof printStr

.code
main proc
	push	offset bytesWritten
	push	printStrSize
	push	offset printStr
	extern	_dllFile:near
	call	_dllFile
main endp

end