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Re: What's the difference between the dialout and tty groups?

On 6/3/18, Martin McCormick <martin.m@xxxxxxxxxxxxxx> wrote:
> 	I added myself to both the dialout and tty groups on a
> stretch installation in order to use the serial ports from the
> user level.  It works fine.  Then I looked at a debian jessie
> installation and found that I had only added myself to dialout
> and it still works fine.
> 	What is group tty actually for?
> This is more of an idle curiosity question than it is one of
> something's broken and I need help.
> 	I am a retired systems engineer who setup unix systems
> for coworkers to use so I know you can sometimes have too much
> power at the user level and accidentally make it easier to make a
> mess of things.

Hi, Martin.. I found these descriptions on the Debian Wiki
SystemGroups page [0]:

tty: TTY devices are owned by this group. This is used by write and
wall to enable them to write to other people's TTYs, but it is not
intended to be used directly.

dialout: Full and direct access to serial ports. Members of this group
can reconfigure the modem, dial anywhere, etc.

What's on the System Groups wiki page is about as far as I'm versed in
it. So far, that's been enough *for me*. I, too, have read at least
once out there that we need to be members of as few groups as possible
for computer safety reasons.

Cindy :)

[0] https://wiki.debian.org/SystemGroups

Cindy-Sue Causey
Talking Rock, Pickens County, Georgia, USA

* runs with duct tape *