Very Computer

I'm writting an Isdn4Linux low level driver for a new PCI ISDN card (not yet
available on market).

I already wrote a char mode driver for the card, and I'd like to perform
file ops such as open, close, ioctl
from the ISDN4Linux low level driver I'm writting now.

        ISDN4Linux                       ISDN4Linux Low Level Driver
Char Mode driver

                            open    ------------------------------------->
my_open

I saw  in kernel fs directory functions like sys_open, sys_close, ....  Are
these functions equivalent to user level
open, close,... functions ?

Another problem : looking in /proc/ksyms, I saw that some functions such as
sys_ioctl don't appear in the kernel public
symbol list whereas they are implemented the same way as sys_open, ... which
appear in the list. Is this normal ?

Thanks.

                                            Yann WANWANSCAPPEL