docker-tvheadend/root/etc/cont-init.d/50-gid-video

#!/usr/bin/with-contenv bash

FILES=$(find /dev/dri /dev/dvb -type c -print 2>/dev/null)

for i in $FILES
do
	VIDEO_GID=$(stat -c '%g' "$i")
	if id -G abc | grep -qw "$VIDEO_GID"; then
		touch /groupadd
	else
		if [ ! "${VIDEO_GID}" == '0' ]; then
			VIDEO_NAME=$(getent group "${VIDEO_GID}" | awk -F: '{print $1}')
			if [ -z "${VIDEO_NAME}" ]; then
				VIDEO_NAME="video$(head /dev/urandom | tr -dc 'a-z0-9' | head -c8)"
				groupadd "$VIDEO_NAME"
				groupmod -g "$VIDEO_GID" "$VIDEO_NAME"
			fi
			usermod -a -G "$VIDEO_NAME" abc
			touch /groupadd
		fi
	fi
done

if [ -n "${FILES}" ] && [ ! -f "/groupadd" ]; then
	usermod -a -G root abc
fi