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Old 11-24-2007, 12:12 AM   #1
Registered: Dec 2004
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How do I switch to root user

I'm designing a program that will periodically need to have root privalages periodically. How do I switch over to root from within a qt program. I tried system("su - root"), but I got a message that it must be run in a terminal.
Old 11-24-2007, 01:34 AM   #2
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First of all, the program will need to either be run as root or will have to be owned by root with the setuid flag set on the actual binary. To change to root when using the setuid flag use the seteuid function.
Old 11-25-2007, 05:10 AM   #3
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How does the KDE clock do it? When you click on adjust date and time it asks for the root users password and then suddenly it has root privileges.
Old 11-26-2007, 03:10 AM   #4
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what is this program?
Old 11-26-2007, 03:26 AM   #5
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One approach is to separate out the admin tasks into a separate program, which can then be called with sudo (if your system uses it).

In the case of the KDE clock it is this way: The clock applet runs as the normal user. When the clock applet is told to set the clock it spawns kdesudo (a graphical wrapper to sudo), which runs kcmshell to set the clock. Only the kcmshell process runs with escalated privileges - the clock applet keeps running with normal privileges.


root, sudo

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