Slock

Slock, or the "Simple X display locker", is a display locker for X that aims to be minimal, fast, and lightweight.[1].

Installation

Install the slock or slock-git^AUR package.

Configuration

Configuration is done by editing the config.h header file and then recompiling the package. After configuration you should create a package.

Usage

Simply run slock to lock the screen. You can also provide an argument to be run after the screen has been locked:

$ slock cmd [arg ...]

To unlock the screen, just type your password.

Tips and tricks

Lock on suspend

Create the following service which turns off the monitor and locks the screen.

/etc/systemd/system/slock@.service

[Unit]
Description=Lock X session using slock for user %i
Before=sleep.target

[Service]
User=%i
Environment=DISPLAY=:0
ExecStartPre=/usr/bin/xset dpms force suspend
ExecStart=/usr/bin/slock

[Install]
WantedBy=sleep.target

Enable the slock@user.service systemd unit for it to take effect for the username user.

Block VT switching and prevent killing X

slock recommends blocking VT switching so that the screen lock cannot be bypassed. For the same reason, slock recommends preventing users from killing the X server. See Xorg#Block TTY access and Xorg#Prevent a user from killing X.