Does it mean it is unnecessary to install LXDE?
I wouldn’t say you need to remove LXDE, but when you install it there will also be scripts run at startup to use it when X sessions start. It might be easier to uninstall LXDE and see what needs to be done to run your application in place of LXDE…then add LXDE back in once you know where the changes are.
Make sure you have a DISPLAY environment variable set…“:0” if it is the only X display, “:1” if it is the second X display, so on.
Yes,I have learned it.
Hi, linuxdev.
I have tried something before similar with your post #18.
I just change the system to runlevel 3.
And cp /usr/bin/startx to my mystartx.
Then I add “client” of mystartx to my single app script.
Then I start mystartx with rc.local.
It indeed achieve display app instead of window manager.
But there are split on screen with lines in this way.
The app is based on opengl cuda opencv.
I think there is some service of window manage to support the display of this app.
I can’t confirm it’s right.
Hi anhuimain,
Sorry that I didn’t read all comments here. It is a long thread. Can this problem be reproduced on rel-28.1?
I don’t try it on rel-28.1
From my test, there is a dependency on desktop.
The phenomenon is that xfce4 desktop environment will produce the problem but cinnamon and original rootfs desktop environment don’t produce the problem.
It is also produced by uninstall unity with command line “sudo apt-get purge unity”
I can have a try of rel-28.1. But it may take a long time.
Also if there is a big change of cuda and opencv and opencv, I would not have the ability to change the existed app.
Does it have a big influence on app based on platform r24.2.1 ？
This is the comment from your first one.
Everything seems well running. But several minutes (about 10 minutes) the display becomes blank （black screen ）. The phenomenon is similiar with PC got into power saving mode.
After that, I browser the web and get several ways to solve it, but all failed. Following below.
You didn’t mention xfce4 desktop here, do you try this in next steps?
To me, I would like to know what is going on from kernel side
Sorry , I mistake that you answer comment #24.
On ubuntu desktop , we can set screensave to figure out it (System Setting → Brightness&lock).
But we don’t want ubuntu environment, so I start up app in rc.local with runlevel 3 (disable lightdm switch to text mode).
In that case , we can’t use tools of gnome and unity to config it.
So the screen blank in regular time interval which we don’t want.
I suppose that there are two direction to solve it.
One is change of configure file in filesystem. It’s concerned with X mostly, but I can’t find the proper way.
The other is change of kernel source. I have succeed unblanking textmode by change kernel, but have no effect with app starting with X.
Hi anhuimain,
So the current problem sounds still like how to disable the auto power saving feature on ubuntu?
Yes, That’s we want.
I don’t know if it can be achieved by change kernel.
Are you still on ubuntu?
How about following command?
xset s off
xset -dpms
xset s noblank
Just FYI, on the part of where you are trying to display your app in place of the window manager by edit of startx: You may need to tell startx to start in a specific color mode and/or screen size. The same is true of your app…you may need to explicitly start it in some mode which matches what the X server is running at. Remember…no window manager means no resizing, no special adapting to fit in a particular space. What you see without adjustments at start is what you get.
Hi ,WayneWWW.Thanks.
It’s useful in some case. Maybe I put it in incorrect configure file.
I am trying to find the correct file to put it in.
Hi. linuxdev. Thanks.
Hi. linuxdev. Thanks.
I definitely agree with you.
Because I don’t know to set the color mode and screen size. So there is a lot problem produced.
I am trying to add them in correct place of the system configure file.
If you run in a regular windowed environment you may find some information about what the settings are via “xdpyinfo”.
For general information on X startup see:
man Xserver
man xinit
Note that startx is basically a scripted wrapper to xinit. Some related files are per user. Check out “.xinitrc” and “.xserverrc”.
It’s very useful.
It’s very useful.