Re: [Nasm-users] can't write argv[0] on stdout - solved

[Holger H. <ha...@gm...>]

On Wed, 19 Aug 2009 09:50:17 -0700
"H. Peter Anvin" <hp...@zy...> wrote:

> On 08/19/2009 01:48 AM, Holger Hanrath wrote:
> > On Tue, 18 Aug 2009 21:19:21 +0200
> > Holger Hanrath <ha...@gm...> wrote:
> > 
> > 
> > here is the program what that does what i want in native x86_64:
> > 
> 
> Yes, but inefficient.

true 

> > ; write 3 bytes from argv[0] to stdout
> > ; syscall numbers from asm/unistd_64.h
> > stdout		equ	1
> > write		equ	1
> > exit		equ	60
> > 	
> > 	mov	rax,	write
> 
> Small number... you probably want "mov eax,..." instead.

from the AMD64 Abi:

"3. The number of the syscall has to be passed in register %rax."

Holger