linux下使用汇编语言编写hello world！程序

section .data                           ;section declaration
msg     db      "Hello, world!",0xA     ;our dear string
len     equ     $ - msg                 ;length of our dear string
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     eax,4   ;system call number (sys_write)
       mov     ebx,1   ;first argument: file handle (stdout)
       mov     ecx,msg ;second argument: pointer to message to write
       mov     edx,len ;third argument: message length
       int     0x80    ;call kernel
;and exit
       mov     eax,1   ;system call number (sys_exit)
       xor     ebx,ebx ;first syscall argument: exit code
       int     0x80    ;call kernel