'C-u C-x s ' is same function without question, right? 
that is the shortcut i want to know. Any one better than this one, since 'u' involve second hand.

It makes my original question stupid. 
Sorry about that.

PS, I am really new to EMACS. org mode is almost the only reason to use it. (i know it is powerful, but dont like to remember a lot of shortcuts)

thanks guys.

Bastien <bastienguerry@googlemail.com> wrote:

  

"goodhei8@gmail.com" <goodhei8@gmail.com> writes:

    

When i save all of my file with C+s, I press a lot of y for yes.
      

I think you mean `C-x C-s', right?  

Also note that `C-x s' is M-x save-some-buffers and let you save many
files at once.

    

IMO, the OP has gotten into a bad habit that he needs to break out of:
`C-x s' (i.e. save-some-buffers - without a prefix argument) is a
surgical operation.  He seems to want the bulk operation of `C-u C-x s':
the latter saves all modified buffers, no questions asked.

Thanks,
Nick