Re: kern/39044: spurious '\n' received from USB-Modems

[Matthias Pfaller <leo%marco.de@localhost>]

Matthias Drochner wrote:
> leo%marco.de@localhost said:
> > Removing the
> >                                 (*rint)('\n', tp);
> >    line from ucom.c doesn't seem to harm
>
> Maybe, but to understand what's going on it would help
> to know which of the 3 possible conditions trigger this.
> (status == USBD_CANCELLED || status == USBD_IOERROR ||
> sc->sc_dying)

I inserted:
                logprintf("status = %d, sc->sc_dying = %d\n", status,
                        sc->sc_dying);

The result is:
    Jul  1 14:05:49 joghurt /netbsd: status = 6, sc->sc_dying = 0

status = 6 is USBD_CANCELLED.

Some more investigation showed (and a mail from Matthias Drochner) 
showed, that it is ucomclose calling ucom_cleanup that triggers the 
spurious \n. The \n is inserted into the tty queue at device close time 
and delivered, when I open the device. Is there any reason to to insert 
the \n into the queue when doing a device close?

Regards, Matthias
--
Matthias Pfaller                          Software-Entwicklung
marco Systemanalyse und Entwicklung GmbH  Tel   +49 8131 5161 41
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