Feature request, but must be universallly accepted by ALL blanker authors

[Alan Coopersmith]

On 10/2/20 12:18 PM, Gene Heskett wrote:
> I have now been 3 days looking for a way to disable this blanker, trying
> several methods by way of xset, only to find 15 minutes later that its
> been undone and the blanker kicks in regardless.

xset only controls the screen blanking & power management built into the
X server.  Anything prompting for a password to unlock is from a client
application or window manager/desktop environment, not the X server, and
has its own controls.  (For GNOME 3, this is built into gnome-shell & gdm,
for other environments it may be a standalone program like xscreensaver
or xlockmore.)

> So I am proposing that an env variable be named an agreed upon name, and 
> that its presence totally disables any and ALL screen blanker's 
> regardless of whose desktop of the day is installed.  We can incorporate 
> the setting of this, on launching LinuxCNC, and unsetting it when 
> LinuxCNC is being shut down.

I don't see how LinuxCNC could set an environment variable that will be
detected by programs that started before LinuxCNC was - normally
environment variables are passed on from the process that starts another
process and there's no common API to change one in an already running
process.

Fortunately, there's already an existing script which knows about the most
common screensaver implementations and how to suspend them:

https://linux.die.net/man/1/xdg-screensaver
https://gitlab.freedesktop.org/xdg/xdg-utils/-/blob/master/scripts/xdg-screensaver.in

So LinuxCNC could call xdg-screensaver suspend with the ID of its
control window.

-- 
	-Alan Coopersmith-               alan.coopersmith at oracle.com
	 Oracle Solaris Engineering - https://blogs.oracle.com/alanc