section .data
    string db 11,"Hello World"

section .bss
    string2 resb 12

section .text
global _main
_main:
    xor ecx, ecx ;clear ecx
    mov cl, [string]
    mov [string2], cl ;copy byte signaling length
    mov edx, 1
    looping: ;copy each single byte
        mov al, [string + edx]
        mov [string2 + edx], al
        inc edx
        dec ecx
        cmp ecx, 0
        jg looping
    xor eax, eax
    ret