eatsyscall.asm

; Print a message out
; Aassmbl with:
;        nasm -f elf64 -g -F stabs eatsyscall.asm
;        ld -o eatsyscall eatsyscall.o

section .data
        EatMsg: db "Eat at Joe's!", 10
        EatLen: equ $-EatMsg

section .bss         ; section containing the unintialized data
section .text        ; The code
global .start        ; The entry point
_start:
        mov        rbp, rsp        ; for correct debugging
        nop                        ; keep gdb happy
        mov        rax, 1          ; 1 => write syscall
        mov        rdi, 1          ; 1 => stdout file discriptor
        mov        rsi, EatMsg     ; pointer to the first address in the msg
        mov        rdx, EatLen     ; the message length
        syscall                    ; make the call
        mov        rax, 60         ; 60 => exit syscall
        mov        rdi, 0          ; the 1st argument
        syscall