snap: https://snapcraft.io/ckermit-raymii
when using a USB serial cable, kermit creates a lockfile in /var/lock (for example /var/lock/LCK…ttyUSB0). This is not a command-line parameter, so a user cannot change the path.
This is the plug: https://github.com/RaymiiOrg/ckermit-snap/blob/master/snap/snapcraft.yaml#L52
Write permission is only required for /var/lock/.