Messages in this thread |  | | Date | Sun, 20 May 2001 17:00:51 +0200 | From | Abramo Bagnara <> | Subject | Re: no ioctls for serial ports? [was Re: LANANA: To Pending DeviceNum |
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Alexander Viro wrote: > > On Sun, 20 May 2001, Abramo Bagnara wrote: > > > > It may have several. Which one? > > > > Can you explain better this? > > Example: console. You want to be able to pass font changes. I'm > less than sure that putting them on the same channel as, e.g., > keyboard mapping changes is a good idea. We can do it, but I don't > see why it's natural thing to do. Moreover, you already have > /dev/vcs<n> and /dev/vcsa<n>. Can you explain what's the difference > between them (per-VC channels) and keyboard mapping (also per-VC)? > > Face it, we _already_ have more than one side band.
This does not imply it's necessarily a good idea. We are comparing
echo "9600" > /proc/self/fd/0/speed (or /dev/ttyS0/speed) echo "8" > /proc/self/fd/0/bits (or /dev/ttyS0/bits)
with
echo -e "speed 9600\nbits 8" > /proc/self/fd/0/ioctl (or /dev/ttyS0/ioctl).
My personal preference goes to the latter, but it's a matter of taste (and convention choice)
(echo -n "keymap " ; cat keymap) > /dev/tty1/ioctl (echo -n "font " ; cat font) > /dev/tty1/ioctl
This seems ugly to you?
> Moreover, we have channels that are not tied to a particular device - > they are for a group of them. Example: setting timings for IDE controller. > Sure, we can just say "open /dev/hda instead of /dev/hda5", but then we > are back to the "find related file" problem you tried to avoid.
It does not seems appropriate to permit to change IDE timings using an handle to a partition... nor it seems very safe under a permissions point of view.
-- Abramo Bagnara mailto:abramo@alsa-project.org
Opera Unica Phone: +39.546.656023 Via Emilia Interna, 140 48014 Castel Bolognese (RA) - Italy
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