no ioctls for serial ports? [was Re: LANANA: To Pending Device Number Registrants]

Pavel Machek
2001-05-19T10:24:14Z

Hi!

> > > They might also be exactly the same channel, except with certain magic
> > > bits set. The example peter gave was fine: tty devices could very usefully
> > > be opened with something like
> > >
> > > fd = open("/dev/tty00/nonblock,9600,n8", O_RDWR);
> > >
> > > where we actually open up exactly the same channel as if we opened up
> > > /dev/cua00, we just set the speed etc at the same time. Which makes things
> >
> > Hmm, there might be problem with this. How do you change speed without
> > reopening device? [Remember: your mice knows when you close device]
>
> If you implement it as a filesystem you coould have a settings file in the
> tty filesystem. Something like this:
>
> echo "115200" > /dev/tty/settings

You can currently do

stty 115200

or

stty 19200

when your stdin is serial port. If it is filesystem, you'll have hard
time finding *which* of serial ports it is, followed by opening it.

What about this?

bash < /dev/ttyS0 &
rm -r /dev/ttyS0
how does bash change speed of serial line, then?
Pavel
--
The best software in life is free (not shareware)! Pavel
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