ASM Community

Hi CyberGuy,

int wsprintf(



    LPTSTR  lpOut,	// address of buffer for output 

    LPCTSTR  lpFmt 	// address of format-control string 

    ...	// optional arguments

   );



 

For example: convert eax (ffff) to decimal 65535 (text format to buffer)

.

.data



capt	db 'Deneme',0

format	db '%08ld',0   ; for 000065535  if you want 65535 use '%ld',0

buffer	db 20 dup (0)



.code



main:

	mov eax,0ffffh ; 65535



	call _wsprintfA, offset buffer, offset format, eax

	sub esp,4*3

	call MessageBoxA, 0 ,offset buffer, offset capt, 0

	call ExitProcess , 0

 

sub esp,4*3 for adjust stack pointer (for TASM) MASM automatic adjust stack pointer with "invoke" calls


have nice days

Hi CyberGuy,

All formats are dword (32bit). wsprintf C based API and format parameter is like a key. If you can convert dword to decimal text format is '%d',0 or convert for hex to string hex (eax=1a2b3c4d--> '%lx' --> '1A2B3C4D')


You can one or more register for convert. For example:

.data



format '%ld',0

result   db 'eax = %ld and ebx = %ld',0

...



.code

....

call _wsprintfA, offset buffer, offset format, eax,ebx

 

I have an example. (my old project) All converts with wsprintf. maybe help you.

btw : sorry my bad english :)

xor eax, eax

movsx eax, [ThisVariableIsWORDInSize]  ;sign extend



or



xor eax, eax

movzx eax, [ThisVariableIsWORDInSize]  ;zero extend

EAX now contains the value of the WORD size variable.

Thanks