[BRLTTY] brlapi sysusers and tmpfiles

[Alexander Epaneshnikov]

hello Dave. in light of brltty 6.2 release i am working on updating arch 
Linux

pkgbuild. for many time we used brlapi group for authenticating to 
brl-API. now,
i want to completely switch to upstream systemd and udev support. since 
i want
to keep brlapi group as aurth method. i think i need to add:
   g brlapi - to sysusers file and z /etc/brlapi.key 0640 root brlapi - to
   tmpfile
also i need to do some modifications to systemd units.

my request is this: if you think it helps other distributions, you can add
configure options to do so. i think it will help not only arch Linux, 
but other
distributions who also wants to switch to brltty's systemd support.
--
Sincerely, Alexander.