If you are out of disk, say due to many big xinit.logs, you might want to clean out session directories below /var/opt/thinlinc/sessions. However, if you remove this entire tree, it will no longer be possible to login since the directory is not automatically created:
2016-12-06 12:17:14 WARNING tl-session: mkdir: No such file or directory
(One could also argue that this should be an ERROR rather than a WARNING)
Perhaps /var/opt/thinlinc/sessions should be created if it does not exist?
At minimum, we should enhance the error message.