Run as different user under FreeBSD [closed]

Answer 1

sudo will allow you to run a command as another user.

sudo -u nobody <command>

will run as nobody, even if their login shell is not available.

Answer 2

You can su to an account with the nologin shell if you use the -m option.

Example:

su -m cthulhu -c '/usr/bin/scorpion-stare'

will run the SCORPION STARE command-line utility as the user cthulhu.