Re: make-frame-command with multiple munitors

[Po Lu <luangruo@yahoo.com>]

Pedro Andres Aranda Gutierrez <paaguti@gmail.com> writes:

> OK... a longer answer ;-) the moment you include (top . xxx) or (left
> . xxx) in the (default|init)-frame-alist the vales are taken as
> absolute values in the window manager's space, and Emacs will be
> placed (normally) somewhere in the display that is designated as 0
> (the Linux laptop or MacBook Pro) independently of which display you
> were when you lunched Emacs.

Well yes, that's intentional behavior.  Setting `top' or `left' tells
the window manager to try very hard to place the frame at the specified
location on the screen.  If you want the frame to be placed at the
correct location, you will have to either remove both position
parameters from initial-frame-alist, for it to be positioned by the WM,
or manually specify the position of the monitor you want.

A note about terminology from the POV of Emacs: the normal coordinate
space of a connection to the X server (the connection is referred to as
a "display") is relative to the root window of the display's default
screen.  A screen is then split into different "monitors", which are
potentially overlapping rectangular subsets of the screen's root window,
normally displayed in a single physical monitor, not counting overscan
or underscan.

`top' and `left' coordinates are specified relative to the root window
of the screen, not "in the display that is designated to 0", nor is such
a coordinate system affected by the monitor in which the initial frame
was created.  Where in the root window coordinate system individual
monitors are placed can only be determined by the output of
display-monitor-attributes-list.