Notes for Ubuntu to add startup items for X-based applications

After analyzing the Ubuntu startup process, we know that there are many ways to add startup items when the system is started, such as in/etc/rcX. d/Add a script S99mystart in the directory. sh: This is the most stupid and not very reasonable method. You can also go to/etc/init. add a script in the d/directory and then automatically update the link to/etc/rcX through the command. d/. No matter how you do it, you only need to meet your specific requirements. However, when adding a startup Item for X-based applications, note the following: ------------ analyzed the Ubuntu startup process. We know there are many ways to add startup items when the system is started.
For example, adding a script S99mystart. sh to the/etc/rcX. d/directory is the most stupid and unreasonable method.
You can also add a script in the/etc/init. d/directory and then automatically update the link to/etc/rcX. d/by running the command.
No matter how you do it, you just need to meet your specific requirements.
Note the following when adding a startup Item for X-based applications:
Incorrect practice:
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#! /Bin/sh
/Usr/bin/gtktest & (with background running)
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In this way, the program cannot run after the system is started.
Correct practice:
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#! /Bin/sh
Export DISPLAY =: 0.0 (the DISPLAY settings are determined by the actual situation)
/Usr/bin/gtktest & (with background running)
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OK. Now you know the reason. You do not know the DISPLAY variable in the environment when the script is started and executed by the system. Although X has been started at this time
Therefore, we must add them on our own initiative.