void linux and locking screen on suspend

Question

I have some troubles with using slock with void linux. I tried adding slock as a script to zzz: /etc/zzz.d/suspend/slock

#!/bin/sh
slock

which works in a strange way: if I call zzz, it brings up slock and doesn't suspend until I enter my password and unlock. I moved the script to /etc/zzz.d/resume/slock, now on resume it flashes unlocked screen for a second and then locks the screen, which is not so good but fine.

But there is another problem: closing the lid suspends the laptop but it doesn't lock the screen at all. I thought it might have something to do with acpid. When I disable acpid, closing lid doesn't suspend the laptop, so acpid is definitely responsible for this. I tried to tinker with /etc/acpi/handler.sh, now it looks like this:

                close)
                        # suspend-to-ram
                        logger "LID closed, suspending..."
                        slock
                        zzz
                        ;;
                open)   logger "LID opened" ;;
                *) logger "ACPI action undefined (LID): $2";;

and slock is not executed anyways. I tried removing zzz from handler.sh, then closing the lid doesn't do anything, which means it actually executes zzz when it's present but doesn't execute zzz's user scripts for some reason. I also tried replacing slock with i3lock in both handler.sh (like void wiki suggests) and zzz.d/resume but it's the same. Did I do something wrong or is there another reason for this behavior?

Answer 1

Your initial solution does not work because the shell waits for the slock process to stop before continuing. The easiest (but not best) solution to to make the command slock & which allows processes to continue after. However, this does not guarentee slock will finish running before the device suspends.

The "proper" way to do this would be using xss-lock to call slock, and using xset to lock the screen on command. Both of these can be found in Void's repositories. xss-lock slock would set xss-lock to use slock for locking.

This should work without any additional scripts, as xss-lock is supposed to act on suspend normally. However, suspend-based events have always been buggy, so an additional activation through xset isn't a bad idea.

An example /etc/zzz.d/suspend/slock would be

#!/bin/sh
xset s activate

A similar script could be placed in the respective "resume" file, but the previous issue of an unlocked screen showing up before the lock screen would still appear.

Answer 2

Tinkered this issue like this:

/etc/zzz.d/suspend/01

#!/bin/sh
doas -u ds xsecurelock &
sleep 2

/etc/doas.conf

permit persist :wheel
permit nopass root as ds cmd xsecurelock
permit nopass :wheel as root cmd zzz
permit nopass :wheel as root cmd ZZZ
permit nopass keepenv root as root

You can try to define $DISPLAY for root user in suspend script, but I'm too stupid to solve this.