# section .text                ;section declaration

                     ;we must export the entry point to the ELF linker or
    global _start    ;loader. They conventionally recognize _start as their
                     ;entry point. Use ld -e foo to override the default.

_start:

;write our string to stdout

        mov     edx,len ;third argument: message length
        mov     ecx,msg ;second argument: pointer to message to write
        mov     ebx,1   ;first argument: file handle (stdout)
        mov     eax,4   ;system call number (sys_write)
        int     0x80    ;call kernel

;and exit

        mov    ebx,0    ;first syscall argument: exit code
        mov     eax,1   ;system call number (sys_exit)
        int     0x80    ;call kernel

section .data           ;section declaration

msg     db      "Hello, world!",0xa     ;our dear string
len     equ     $ - msg                 ;length of our dear string