Re: config(5) break down

[Matt Thomas <matt%3am-software.com@localhost>]

On Mar 20, 2010, at 8:37 AM, Masao Uebayashi wrote:

> On Sun, Mar 21, 2010 at 12:14 AM, Matt Thomas 
> <matt%3am-software.com@localhost> wrote:
>> Which is fine if you have one type of serial port, but if you have a mix of 
>> devices all providing serial ports how do you know what tty is going to what 
>> serial port (especially with multiport serial devices)?
> 
> Like puc(4)?  It has an array of ports (sc_ports) where child com(4)
> device_t pointers are stored.  com(4) has sc_tty.  So you can lookup
> puc->com->tty.
> 
> FreeBSD's tty(4) stores its serial device's softc as t_devswsoftc.  I
> think we can make tty(4) as a device so that we can lookup
> tty->com->puc using dv_parent.

I'm talking about <maj, min> to device.  How, as a user, do I know what actual 
tty does /dev/ttyXX open?