Runas is a tool for running commands as another user.  It is an
alternative to "sudo", which has a history of serious security issues,
and "su", which is inconvenient for anything but running a shell.

The runas command is a simple wrapper around "su" to streamline its
use.  It differs from "sudo" in that it requires the password of the
target user rather than the calling user, and it requires no SUID
permissions or configuration.