Re: serial port (USB) permissions

From: Arthur Chance <freebsd_at_qeng-ho.org>
Date: Wed, 06 Aug 2025 15:59:14 UTC 
On 06/08/2025 13:32, Johan Helsingius wrote:
> Hi,
> 
> Connecting a serial adapter to the USB port works otherwise
> OK (shows up as /dev/ttyU0, but seems only root has access
> to the port. I am used to some group like "dialout" having
> access as well. Is there some setting for allowing ordinary
> users access. or do I have to do a chmod every time I connect
> the device?

Take a look at man devfs.rules (and maybe man devfs).

You want a local ruleset and a rule something like

add path /dev/ttyU* mode 0660 group dialer

You'll also need to set devfs_system_ruleset in /etc/rc.local to use the
new local ruleset.

-- 
We should have listened when the modems screamed at us.