Change permissions on /dev file?

[Toralf Lund]

>>>> How can I update permissions on a device file on an FC4 setup? I 
>>>> mean, I know I can use chmod, of course, but the problem is that 
>>>> for /dev special files, the changes are lost on reboot. [ ... ] 
>>>
>>>
>>>
>>> grep -n "sg" /etc/udev/permissions.d/50-udev.permissions
>>>  
>>>
>>> The permissions are set there.
>>>  
>>>
>> Right. I haven't quite got used to this new(ish) udev stuff... Seems 
>> to me now it must be the place for the setting I want, but the 
>> location you mention can't be correct for my system, as /etc/udev has 
>> no permissions.d.
>>
> Look to /etc/udev/rules.d
> HTH

I think I should be able to define an appropriate rule for my unit, but 
I'm surprised to find that the udev doc does not mention a key 
containing the device type or vendor/product id (as reported e.g. in 
/proc/scsi/scsi.) Is there really now way to do direct match on those?

- Toralf