i3lock is a simple screen locker like slock.
This SlackBuild patches i3lock to not to use PAM, and is as such usable in
Slackware.
For verifying the password it uses shadow instead. Because of that, it needs
suid permissions, but those privileges are dropped as soon as possible.
The code for this was taken from slock. See the patch and LICENSE-slock.
NOTE: Version 2.9-1_SBo is patched to revert this commit:
https://github.com/i3/i3lock/commit/80d4452ec680bcb0e57418f69d44d88ded82047c
See the SlackBuild for more info.