[Nasm-users] Re: [win32-nasm-users] windows shutdown

[Frank K. <fbk...@co...>]

nmt wrote:
> 
> I've seen here some codes to logoff from windows, but any source code
> to shutdown any windows version platform; so that I wrote theses codes
> that work in 9x, NT, 2000, XP (and suposse that run in 2003).
> 
> http://mipagina.cantv.net/porrasgarcia/shutdown.zip
>   
> Sorry by this style to write NASM codes, but is the easiest way that I
> found to assemble programs using only NASM, without any linker.

Very cool! But there's a bug in it! Being a die-hard dos-head, I 
actually *tried* the dos stub, and I got garbage before the "this 
program requires win32!" message. Stepping through it, I also noticed 
that the "call @w" generates the wrong address! We're executing the "!$" 
at the end of the data!!! I did this to it:

stub:
bits 16  ; <-
        call .@W
        db "This program only runs in win32!$"
	.@W
        pop dx

        push cs   ; <-
        pop ds    ; <-

        mov ah, 9
        int 21h
        mov ah, 4ch
        int 21h
        ...

...and it seemed to work a little better. If anyone cares whether the 
dos stub works, these days...

This particular program could benefit from a custom stub which actually 
reboots, instead of whining about not finding 'doze. I guess the 
"safest" way to reboot from dos is to emulate control-alt-delete(?). I 
can't lay my hands on an example of that code right at the moment, but 
I'm sure I can figure it out. I *did* come across a three-byte reboot 
example:

     pop sp
     inc sp
     push sp

I don't think that's so safe, and it may not work on all systems, but it 
reboots my machine, and it sure is short :)

Anyway, thanks for posting that, Numa (and for the Xwindows examples! - 
and gigathanks to Yeoh for the steady stream of examples!). This is 
really turning into a goldmine!

Best,
Frank