physlock

locks all virtual consoles and prevents unauthorized access to the system

TLDR

Lock all consoles

$ physlock

Lock and mute kernel messages

$ physlock -m

Lock and disable SysRq

$ physlock -s

Lock with custom message

$ physlock -p "[Locked!]"

Lock and detach (for suspend scripts)

$ physlock -d

SYNOPSIS

physlock [-d] [-m] [-s] [-p message] [-l]

physlock locks all virtual consoles and prevents unauthorized access to the system. Unlike screen lockers that only protect graphical sessions, physlock secures all TTYs, preventing access through Ctrl+Alt+F1-F6 switching.Authentication is required from the current user or root to unlock. This makes it suitable for securing systems with physical access concerns, particularly servers or kiosks.

PARAMETERS

-d

Fork and detach (daemonize)

-m

Mute kernel messages while locked

-s

Disable SysRq key while locked

-p _message_

Display message before password prompt

-l

Only lock the current tty

INSTALL

sudo apt install physlock

sudo apk add physlock

sudo zypper install physlock

nix profile install nixpkgs#physlock

CAVEATS

Does not lock graphical displays; use alongside a screen locker (e.g., i3lock, slock) for X11/Wayland sessions. Requires PAM for authentication. Detach mode (-d) is useful in suspend/hibernate scripts (e.g., systemd sleep hooks). SysRq disable is only effective if the kernel has CONFIGMAGICSYSRQ enabled. Must be run as root or with appropriate permissions.

HISTORY

physlock was created by Bert Muennich as a lightweight alternative to vlock. It focuses on securing physical console access with minimal dependencies, making it suitable for embedded and minimal systems.