Re: Why the C-M-<keys> is invalid in my emacs?

[Navy Cheng <navych@126.com>]

On Fri, Aug 07, 2015 at 08:12:59PM -0700, Rusi wrote:
> On Saturday, August 8, 2015 at 8:40:59 AM UTC+5:30, Navy Cheng wrote:
> > On Fri, Aug 07, 2015 at 07:42:57PM -0700, Rusi wrote:
> > > On Saturday, August 8, 2015 at 7:26:56 AM UTC+5:30, Navy Cheng wrote:
> > > > Hi,
> > > > 
> > > > I find I can't use *C-M-<keys>* combined key in my emacs. I have to use
> > > > *Esc C-<keys>* to instead. However, when I close X-server in my OS and
> > > > use emacs in the console, *C-M-<keys>* is OK.
> > > > 
> > > > Why? How can I use *C-M-<keys>*, such as *C-M-h* in X?
> > > > 
> > > > Thanks.
> > > 
> > > Probably this is OS-related
> > > And you need to tell which OS so that those who know more specifics can answer.
> > > Also 'M-' means what exactly to you?
> > 
> > I use Debian 8 and Xfce Desktop Environment. 'M-' is OK and 'C-M-' is OK in other
> > software execpt emacs.
> 
> What physical hardware key is 'M-'?

'M-' is Alt, 'C-' is Ctrl.