How to request root permissions in an application?

Question

linux

Actually, you need to ask the user for privilege escalation to perform the operation (For example: as Steam does during installation or Update Manager). How can this be implemented? Maybe there are some system calls for this?

Answer 1

Look towards any kdesu, gksu, etc.

Answer 2

See also how Qt Installer Framework 1.5.0
works. It asks for root permissions (password entry) if you try to write something to a directory that is not writable by a regular user.