properly way of setting premissions for devices in /dev/

[Ramiro Aceves <ea1abz%gmail.com@localhost>]

Hello all,

I have been making fun experimenting with ham/rtl-sdr package in
raspberry pi 4 on NetBSD.
After some failures trying to get it work as a normal user instead of
root, I came to the conclusion that I should change the permissions of
these two files in /dev/ugen to be used by the "wheel" group I belong
to.

original files permission:

crw------- 1 root wheel 72, 0 Jun 30 19:58 ugen0.00
crw------- 1 root wheel 72, 1 Jun 30 19:58 ugen0.01

files after permissions change:

crw-rw---- 1 root wheel 72, 0 Jun 30 19:58 ugen0.00
crw-rw---- 1 root wheel 72, 1 Jun 30 19:58 ugen0.01

That works fine to make the receiver work as wheel group user..

Before knowing that those two files were the right ones, I was
desperately  tweaking /dev/usb* files. Receiver started to work as
normal user.  Then I removed the permisions to usb files expecting the
receiver stop working as normal user, but the receiver continued to
work. I was then  puzzled.

The only explanation for that is that I did a mistake and issued  a
"chmod 660 usb  *" command in /dev/ instead "chmod 660 usb*"  so the
receiver started to work "brute force" ;-).

So I believed that I screwed up all /dev/ permissions. I did a "sh
MAKEDEV all"  in /dev/ directory as read in a Install.html document on
the NetBSD repositories but after a while I read that it should be
done in single user mode.

I followed the procedure " 22.7. How to rebuild the devices in /dev"
in The NetBSD Guide to restore them using sh MAKEDEV all in single
user mode. I think  that they were restored fine :-)

Manual file permissions change on /dev/ugen files worked flawlessly.
But my concern is if that should be configured somewhere else
(something like udev rules in linux) or I did it right.

Because I rebooted the system there was nothing at sh shell history, I
would be a good thing being able to know what I did. I think that
NetBSD sh does not have the posibility of configuring a history file
to record the past commands, but not sure. Am I right? That would be a
good thing.

Thanks so much in advance.
Ramiro.