;;; nasm -f elf64 hello.asm && ld -o hello hello.o && ./hello
        bits 64
section .text
global _start
_start:
        mov rax, 1
        mov rdi, 1
        mov rsi, msg
        mov rdx, len
        syscall

        mov rax, 60
        xor rdi, rdi
        syscall

section .data
        msg     db      'Hello, world!'
        len     equ     $ - msg