Re: Linux-2.4.20 modem control

Richard B. Johnson (root@chaos.analogic.com)
Mon, 17 Mar 2003 16:12:28 -0500 (EST)


On Mon, 17 Mar 2003, Jamie Lokier wrote:

> Richard B. Johnson wrote:
> > Now, the hang-up sequence appears to be queued. It can (and does)
> > happen after the previous terminal owner has expired and another
> > owner has opened the device. This makes /dev/ttyS0 useless for remote
> > log-ins.
> >
> > It needs to be, that a 'close()' of a terminal, configured as a modem,
> > cannot return to the caller until after the DTR has been lowered, and
> > preferably, after waiting a few hundred milliseconds. Without this,
> > once logged in, the modem will never disconnect so a new caller
> > can't log in.
>
> Better would be if the hang-up sequence is still queued, but a new
> open() is delayed until the hangup has completed.
>
> -- Jamie
>

Yes, something like that. Modems are "special" only one task is
going to access that device at one time.

Cheers,
Dick Johnson
Penguin : Linux version 2.4.20 on an i686 machine (797.90 BogoMips).
Why is the government concerned about the lunatic fringe? Think about it.

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