RE: Multi-head session management

["bharat tewari" <bharat tewari wipro com>]

hey jacob
thx. for summarizing this mail chain. This falls exactly with the line of
the design that we were planning to propose too.

i propose a '--screen' argument, parsed by the x11 gtk backend (or
libgnomeui, if we have to).  this argument will override the screen
portion of the display name in --display or $DISPLAY.  if XOpenDisplay()
fails with this screen, then the default --display or $DISPLAY is used.

more elaboration
a) if "screen" option is parsed by gtk : no issue, if the screen is not
available, then we can easily fall back upon the default display
b) if libgnomeui is used to parse "screen" : in that case, the "display"
parameter will be munged hence within gtk if XOpenDisplay() fails then we
can only use the environment $DISPLAY variable to set the correct display as
"--display" will be already overwritten.
In both cases, there will be added code in gdk x11 backened code wherein we
need to check the XOpenDisplay() with both parameters. In addition, do we
need to change the other backends like win32 etc. for this or it is not
required.


the session manager will not do any munging of $DISPLAY variables or
--display command line arguments.

the current CDE session management does this. It is the one which keeps
track of the screen and sets the display accordingly before launching the
applications. However for us, we will do the same in either gtk or
libgnomeui.