Identifying the real display server

[Thiago Macieira]

On Saturday 11 April 2015 00:33:50 Mattias Andrée wrote:
> Is there another way to identify which display server is
> actually running? If not, I propose we add the environment
> variable REAL_DISPLAY. The value of REAL_DISPLAY should be
> then name of the environment variable used by the display
> server that is actually running. For example if Wayland is
> running with an X compatibility layer, the value of
> REAL_DISPLAY should be WAYLAND_DISPLAY.

I'd recommend having one common variable that lists all the options, in the 
order of preference of the compositing server. Suppose it's a Wayland server 
with Mir and X compatibility layers and the X layer is better supported, we'd 
have:

 wayland:///run/user/1000/wayland-0|x11::0|mir:///run/user/1000/mir-0

I chose to use the pipe character (|) because it cannot appear unencoded in 
URLs, so you can easily tokenise and parse each item as a URL. The space 
character would have served just as well.

As for the name of the variable itself... I'll leave the bikeshed to others 
:-)

-- 
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
   Software Architect - Intel Open Source Technology Center
      PGP/GPG: 0x6EF45358; fingerprint:
      E067 918B B660 DBD1 105C  966C 33F5 F005 6EF4 5358