.data
buf: .fill 1
counter: .fill 4
linecounter: .fill 4
.text
.global _start
_start:

    movl $0,counter
    movl $0,linecounter
LoopBegin:
    movl $3,%eax
    movl $0,%ebx
    movl $buf,%ecx
    movl $1,%edx
    int  $0x80
    
    cmpl $0,%eax
    jz   CondEnd
    # %eax is nonzero, we read a char
    cmpb $'\n',buf
    jnz  CondEnd
    # add one to linecounter
    addl $1,linecounter
CondEnd:
    
    addl %eax,counter
    
    cmpl $0,%eax
    jnz  LoopBegin
    
LoopExit:

    movl $1,%eax
    movl $0,%ebx
    int  $0x80