I would like to configure CentOS7 (KDE4) computers with two screen into a special configuration. I have done that before on CentOS5 (KDE3), and now I have to migrate to CentOS7 (and preferably to CentOS8 (KDE5?) when it is available).
I have configured X already to have two screens the way I want them. One is
:0.0 and the other is
:0.0, I have to run a fullscreen application, which has to have mwm (Motif Window Manager). mwm and the application work fine on screen
Now it comes the complicated part. On another screen
:0.1, I would like to run KDE, which I will customize. On CentOS5, that was not a problem, since I started kwin, kicker, and kdesktop on that screen by setting
DISPLAY environment variable properly. That was enough to have basic KDE functionalities I need there.
Newer KDE is more complex and I cannot start it so simple. Whatever I do, it starts on both screens or does not start at all. I have managed to start kwin. It works, but it writes a lot of error messages on stdout/stderr.
Is there a way to make KDE run on display
:0.1 only, and leave
:0.0 alone? For me it seems like programmers forgotten about displays, so it seems that some programs within KDE environment are aware of it, while others occupy all displays available. Plasma desktop does seem to ignore every display setting I have tried.
I guess I could run two different window managers on two screens if I started two XServers, but multiseat configuration (https://lxadm.com/Configuring_multiseat_X_workstation) is not the solution I am looking for in this case. Multiseat config then has displays
:1, and brings two completely separate sets of mice, keyboards, cursors on screen. That is not acceptable. I need one keyboard and mouse to go from one screen to another.
The functionality I need on that screen is to have a customized taskbar, where users can start only allowed applications available there. They shall not have access to other apps. This can easily be accomplished with KDE, but now I have problems with running it on one screen only.
I am not sure I will be able to pull this off with KDE, which is available in CentOS7. Maybe I should try it with GNOME, which is not so highly customizable as KDE. For the first test it started only on one display and did not mess with
:0.0. However, I am not sure I can limit its use as I can in KDE.
Is there some other desktop environment, which would provide simple configurable taskbar and would not mess with the window manager on another screen? I am thinking about trying xfce.