;; Hello world! using syscalls.  Modified from:
;; http://www.linuxgazette.com/issue53/boldyshev.html
;; Author: Konstantin Boldyshev
	section .text		 ; Code section
	global _start            ; Linker needs this symbol.

;; This is the starting symbol.  In a C program, _start is a library function
;; which perfoms initialization, then calls main.  For this, we'll just start
;; here.
_start:
	;; Load the syscall parameters into expected CPU registers.  Linux looks
	;; for the syscall code in eax, and any parameters in ebx, ecx, edx,
	;; esi, edi and edp, in that order.
        mov     ebx, 1   	; First parm, file stream 1 (standard output)
        mov     ecx, msg 	; Second parm, pointer to the buffer.
        mov     edx, len 	; Third parm, message length.
        mov     eax, 4   	; Syscall number (sys_write).
        int     0x80    	; Syscall instruction.  Enters kernel.

	;; Now we need to exit.  Just falling off the end won't work.  Need
	;; to tell the kernel that we need terminating.
        mov     eax,1   	; System call number (sys_exit)
        int     0x80    	; Syscall instruction.

	section	.data		; Data section
;; This declares a string of characters to write, and computes its length.
msg:	db      'Hello, world!',0xa     ; 
len:	equ     $ - msg                 ;