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The  (substitute user) command can be used to impersonate other users on the system. is provided by the package. It is also included with the package, but it is disabled in the ebuild to prevent a file collision with.

Usage
will run commands as root by default. Since not specifying a username will cause to ask for root privileges, the following command will run as root and halt the system:

It is also possible to specify a user other than root to substitute commands. The following example will run the command as the user larry: