Ubuntu

Run application from GDM

Asked by Stuart Smith

Hi,

I am a bit of a Linux newbie but I was wondering if it is possible to add a button to the Ubuntu logon screen which then executes a GUI application. This functionality is provided in MS Windows via the GINA.

I need to be able to click the button which opens the GUI application. I know security can be a concern but the application only makes calls to an external web service so there is no system related code being executed. I am a bit confused as to provide this functionality in Ubuntu.

I notice XDMCP menu item on the logon screen seems to provide the functionality I require (for example - hit the button and it seems to restart the Window Manager (I may be wrong here ;-)) and fire up a GUI application).

Is there anyway that I can implement this functionality myself. I have tried looking for the source code for where this function is handled but I don't know where to start!

Many thanks for your assistance,
Stuart Smith

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phoozle
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Revision history for this message
Micah Gersten (micahg) said : 		#1

Are you trying to make a kiosk?

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phoozle (phoozle) said : 		#2

I'm a bit unsure but maybe this will help:

http://library.gnome.org/admin/gdm/2.26/configuration.html.en#autostart

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Stuart Smith (ssmith-tools4ever) said : 		#3

Hi,

The above solution doesn't solve my problem. I need to be able to create a menu item at the Ubuntu logon screen which executes a GUI based application.

I can execute terminal based applications via the Edit commands dialog in the Login Window administration applet. But I cannot work out how to open a GUI based application.

As stated earlier if you click the XDMCP menu item it opens a GUI for connecting to a remote system. I need to provide similiar functionality for an application I have developed myself.

Many thanks, for your assistance
Stuart Smith

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phoozle (phoozle) said : 		#4

Hi again.

Just having some ideas. What if you were to start a basic X session under an underprivileged user and run the application desired. Create a shortcut button on the desktop or somewhere which kills that X server and starts GDM allowing users to login.

I found this also. They might know a better way:
http://www.nabble.com/How-can-I-run-a-GUI-application-before-gdmgreeter--td22795544.html

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Stuart Smith (ssmith-tools4ever) said : 		#5

Hi,

Thank you for your answer. Starting an X session definitely sounds the way to go! :)

Would you mind explaining how I might go about this as I am still new to Linux. Is there anyway you can provide an example of how I might start an X session as an underprivileged user and run a GUI application for example gedit or something?

Many thanks,
Stuart

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Best phoozle (phoozle) said : 		#6

I would prefer to do this away from Launchpad. Just mark my last answer to you as solved.

Contact me at <email address hidden> and I can reply with some instructions.

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Stuart Smith (ssmith-tools4ever) said : 		#7

Thanks phoozle, that solved my question.