Re: Unwanted auto-assertion of DTR & RTS on serial port open

On Mon, 23 May 2022, Mychaela Falconia wrote:

> Hello,
>
> I am not a current FreeBSD user (I use Linux at the moment), but I am
> asking here in connection with this recent feature addition to FreeBSD:
>
> https://reviews.freebsd.org/D20031
>
> The main purpose of this inquiry is to find out if this newly added
> FreeBSD feature really works as it seems at first glance, or if it is
> not quite there yet.

The man page adds the (-)rtsdtr option in version 13.1:

    https://www.freebsd.org/cgi/man.cgi?query=stty

and I can confirm it is an invalid argument in 13.0. I can't confirm that 
it works in 13.1, though, only that it is first documented there. You 
should be able to test it with any old desktop computer pretty easily 
though. Documented things tend to work.

Have you thought of the alternative solution of cutting some wires in the 
serial cable? Does your device even need those signals? Would it work at a 
lower data rate?

This does remind me of a question I have had myself - which is how does 
one tell from the bugzilla or review what version a commit refers to? 
Bugzilla has a Version descriptor, but presumably that refers to the 
version where the bug is found, not where it is corrected. The word 
"version" does not appear on the typical Review page.

Daniel Feenberg
NBER