[BRLTTY] lock on device

[raoul mégélas]

Le Sat, 31 Mar 2007 22:36:14 +0200
Samuel Thibault <samuel.thibault at ens-lyon.org> wrote:


Hi Samuel,

> It's been some time since this was raised, I at last took some time to
> have a look at BSD documentation.

> Raoul MXgXlazs, le Sun 25 Feb 2007 16:52:43 +0100, a écrit :
>> FreeBSD defines a lock on the sio and uart ports.
>> This lock avoid to the user or a program to change the port parameters.
>> To the parameters of the port we have to set the parameters to
>> DEV.init say cuaU0.init for first usb to serial, or cuau0.init for
>> the first serial, and so on.
>> for a device...

> Why should we tinker with DEV.init at all?  Don't ioctls() on DEV
> already work fine?  From the documentation I could read, DEV.init is
> just used for the system default settings, and DEV.lock is for the
> imposed settings.

that's true! and ioctl() works fine effectively.
(in all case, i learned two things:
1. to look at the doc tiil the end!
2. using the ioctl() avoid the lock).

> Brltty should probably not modify them...

except of course if they are wrong (115200 for instance),
or perhaps, to protect brltty against any change from an other program.

best regards

raoul