/usr/share/vdr/groups.d/vdr-plugin-dvd.groups is in vdr-plugin-dvd 0.3.6~b03+cvs20090426.0013-24.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | #
# The DVD plugin requires vdr to be a member of the group 'cdrom' in order to
# get access to the DVD drive.
#
cdrom
|