Re: Use of :@ on mode line

[Eli Zaretskii]

> From: Kevin Buchs <kevin.buchs@gmail.com>
> Date: Thu, 1 Dec 2016 08:16:40 -0600
> 
> I'm running GNU Emacs 25.1.1 (x86_64-apple-darwin15.6.0, NS appkit-1404.47
> Version 10.11.6 (Build 15G1004)) graphically and since I started running
> it, I'm seeing an extra character on the mode line. Where there was just a
> colon between CS and CH, there is now :@. What does that mean? It isn't
> documented in the Info manual:  (info "(emacs) Mode Line") nor do I see it
> in the What's changed section of the Info manual.
> 
>  Example mode lines:
>   - Reading an Info page in info-mode:   U:@%%-
>   - Buffer created and changed: U:@**-
>   - File opened and unchanged: U:@---

Crystal ball says you are running via emacsclient, perhaps your Emacs
is a daemon?

This character indicates that the frame was created by emacsclient.
You are right, it wasn't documented in the manual that shipped with
Emacs 25.1, but it is documented now in what will shortly become Emacs
25.2.