In Xinerama/Panoramix configuration there's one screen that's having special
meaning - it's used for simulating as the frontend for all client operations:
the clients (should) only talk to that screen, while panoramix subsystem is
proxying those operations to all the other screens (with certain changed
applied, eg. coordinate transformations).
Historically, this screen happens to be the first one in the system (some of
it's proc's are hooked up in order to achieve desired behaviour). That's why it
used to be accessed via screenInfo.screens[0] - that already had been encapsulated
into a tiny helper `dixGetFirstScreen()`.
a) the correct terminus technicus for a situation where one device (or SW entity)
entirely controlling others is a master-slave-relationship: the controlling
device/entity is `master`, the controlled ones are `slave` (to that specific
master).
b) the term "first screen" is inacurate and misleading here: what the caller's are
actually interest in isn't the first entry in the screen array, but the screen
that's controlling the others. With upcoming refactoring of the Xinerama/Panoramix
subsystem, this might well be a different array index than 0.
c) the term `default` also wouldn't match: `default` implies there's a real practical
choice, and such value applies when no explicit choice has been made. But in this
case, it practically doesn't make sense (except perhaps for debugging purpose)
for a client to use any different screen.
Therefore fixing the function name to the correct technical terminology.
(for sake of patch readability, renaming corresponding variables is left to
subsequent patches).
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
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