A syscall quiz

Makefile

all: quiz

quiz.o: quiz.asm
	nasm -f elf64 $< -o $@

quiz: quiz.o
	ld -Tdata=0x8000000000 $< -o $@

quiz.asm

[bits 64]

global _start

_start:
    mov rdx, 12
    mov rcx, 0x8000000000
        or rcx, R
    mov rbx, 1
    mov rax, 4
    int 80h
    mov rdx, 12
        mov rcx, S
    mov rbx, 1
    mov rax, 4
    int 80h
    mov rdx, 12
    mov rsi, T
    mov rdi, 1
    mov rax, 1
    syscall
    mov rax, 60
    syscall

R:
db "Oh no world", 0x0a

; NB: will be linked with
; ld -Tdata=0x8000000000
[SECTION .data]
S: 
db "Hello world", 0x0a
T:
db "Goodbye foo", 0x0a