global _start
 
section .data
        buffer  dw      0h
 
section .text
 
_start:
        mov             ecx, buffer
        mov             edx, 02h
        call            read
        mov             cx, word [buffer]
        cmp             cx, 3234h
        je              exit
        cmp             ch, 0ah
        je              one_dig
        jmp             two_dig
 
one_dig:
        mov             ecx, buffer
        mov             edx, 02h
        call            write
        jmp             _start
 
two_dig:
        mov             ecx, buffer
        mov             edx, 02h
        call            write
        mov             edx, 01h
        mov             ecx, buffer
        call            read                    ; read the 0ah
        mov             ecx, buffer
        call            write                   ; write the 0ah
        jmp             _start
 
exit:
        mov             eax, 01h                ; exit()
        xor             ebx, ebx                ; errno
        int             80h
 
 
read:
        mov             eax, 03h                ; read()
        mov             ebx, 00h                ; stdin
        int             80h
        ret
write:
        mov             eax, 04h                ; write()
        mov             ebx, 01h                ; stdout
        int             80h
        ret