Specifications

# see http://roadrunner.swansea.uk.linux.org/v4lapi.shtml
echo "*** new device names ***" makedev video
0 makedev radio 64 makedev vtx 192 makedev vbi 224
# "*** old device names (for compatibility only) ***"
#makedev bttv 0 #makedev bttv−fm 64 #makedev bttv−vbi 224
Simply copy and paste the above into your favorite editing program, save it as MAKEDEV or whatever name
you like, make it executable (i.e., chmod u+x MAKEDEV), and then execute it as root:
# ./MAKEDEV
3.4. Groups and Permissions
It is a good idea to be sure that your user account can access the device once all modules are loaded and
device nodes created. The most security−conscious way to do that is to add access for a particular group. On
my system, the members of the group 'video' are allowed to use the webcam, scanner and other photographic
devices. The way to accomplish this is to first change the ownership of the devices in /dev like so (as root):
# chown root.video /dev/usb/video*
...where root.video are the owner and group the device will now belong to. Obviously, the specific command
will vary by your system and the type of device. It is important that you change the ownership of the device
node itself and not the symlink; symlinks' ownerships are affected only by changing the parent devices or files
they point to.
To see if your user account is a member of the group in question, as root issue the following command:
# grep −e video /etc/group
You should see something like the following:
video:x:44:
...where '44' is the group number. Since no members follow the last colon in the 'video' group, we can add
them, let's say user 'jhs' with the command
# adduser jhs video
After this, it's simply a matter of allowing read and write access for the user in question of the device like so:
# chmod g+rw /dev/v4l/video0
...where g+rw means add read and write access for group. See the documentation for chmod (man chmod or
info chmod) for further info.
The BTTV HOWTO
3. Enabling Support for Your Bt8x8 Hardware in Linux 8