section .data
    buf: db 'hello world',10
section .text
    global _start
_start:
    mov eax,4  ; write(ebx=1, ecx="buf", edx=12);
    mov ebx,1
    mov ecx,buf
    mov edx,12
    int 80h    ; syscall
    mov eax,1 ; exit(ebx=0)
    mov ebx,0
    int 80h   ; syscall