get usb device descriptor through ioctl?

[thomas nivelet <lugarbleiz%gmail.com@localhost>]

thank you all for your answer

>The umodem(4) man
>page refers to the ucom(4) man page, which says that the files are
>/dev/dtyU? and /dev/ttyU?.  You have to read the MAKEDEV script itself
>to figure out that a command like "MAKEDEV ttyU0 ttyU1 ttyU2" will
>create all of the /dev/{tty,dty,cty}U[012] devices.

the good news: dtyU? and dev/ttyU? already exist so I don't have to create them
the bad news: opening them with "open("/dev/dtyU0", O_RDONLY);" or
"open("/dev/ttyU0", O_RDONLY);" crash my system: with the following
error message:

ucom0 at umodem0
ucom0: ucomreadcb: zero length xfer!
fatal page fault in supervisor mode
trap type 6 code 0 eip c060e64c cs 8 eflao break