physlock
Lock all consoles and virtual terminals.
TLDR
Lock every console (require current user or root to unlock)
$ physlock
Mute kernel messages on console while locked
$ physlock -m
Disable SysRq mechanism while locked
$ physlock -s
Display a message before the password prompt
$ physlock -p "[Locked!]"
Fork and detach physlock (useful for suspend or hibernate scripts)
$ physlock -d