SECTION .data
   
msg: db "hello world!", 0x0a
len: equ $-msg
  
SECTION .text
global _main
  
kernel:
     syscall
     ret
 
_main:
     mov rax,0x2000004
     mov rdi,1
     mov rsi,msg
     mov rdx,len
     call kernel
  
     mov rax,0x2000001
     mov rdi,0
     call kernel