Alessandro Mauri
fe9d88e7f9
implemented -e flag: it copies the elements of env that we want to keep, clears the environment and sets it to only the saved and default elements. also removed the code for copying the environment and allocating a new one
US - User {Switcher,Shell}
Opens a shell as a different user without needing to authenticate as that user.
This is similar to the behavior of su but it allows to execute privileged
and/or commands as any other user without needing their password.