trusty (4) isdninfo.4.gz

NAME

       isdninfo - ISDN status device

SYNOPSIS

       #include <linux/isdn.h>

DESCRIPTION

       /dev/isdninfo  is  a  character  device  with  major  number 45 and minor number 255.  It delivers status
       information from the Linux ISDN subsystem to user level.

DATA FORMAT

       When reading from this device, the current status of the Linux ISDN subsystem is delivered in 6 lines  of
       text. Each line starts with a tag string followed by a colon and whitespace. After that the status values
       are appended separated by whitespace.

       idmap  is the tag of the first line. In this line  for  every  virtual  channel,  the  Id-string  of  the
              corresponding lowlevel driver is shown. If no driver is loaded, a - (hyphen) is shown.

       chmap  is  the  tag  of  line  2.  In  this  line  for  every  virtual channel, the channel number of the
              corresponding lowlevel driver is shown. If no driver is loaded, -1 is shown.

       drmap  is the tag of line  3.  In  this  line  for  every  virtual  channel,  the  index  number  of  the
              corresponding lowlevel driver is shown. If no driver is loaded, -1 is shown.

       usage  is  the  tag  of  line  4. In this line for every virtual channel, the current usage is shown. The
              following usage constants are defined:

              ISDN_USAGE_NONE (0)
                     Unused channel

              ISDN_USAGE_RAW (1)
                     Channel used by raw device (currently unsupported)

              ISDN_USAGE_MODEM (2)
                     Channel used by some ttyI

              ISDN_USAGE_NET (3)
                     Channel used by an ISDN net-interface

              ISDN_USAGE_VOICE (4)
                     Channel used by some ttyI in voice mode.

              ISDN_USAGE_EXCLUSIVE (64)
                     Channel exclusively preserved for a net-interface. This value is logically or'ed  with  one
                     of the other codes.

              ISDN_USAGE_OUTGOING (128)
                     Channel  is used outgoing. This value is logically or'ed with one of the other codes. It is
                     set, when dialling is started and reset, when  either  dialling  failed  or  after  hangup.
                     Therefore,  it  is not always an indicator for an established connection. To get a reliable
                     indicator for an established connection, the driver flags (see below) have to be  inspected
                     also.

       flags  is  the  tag  of line 5. In this line for every driver slot, it's B-Channel status is shown. If no
              driver is registered in a slot, a ? is shown.  For every established B-Channel of  the  driver,  a
              bit  is  set in the shown value. The driver's first channel is mapped to bit 0, the second channel
              to bit 1 and so on.

       phone  is the tag of line 6. In this line for every virtual channel, the remote phone number is shown  if
              the channel is active. A ??? is shown, if the channel is inactive.

BLOCKING BEHAVIOUR

       After opening the device, at most 6 lines can be read by a user process.  After that, the user process is
       blocked. Whenever a status change happens, the process is allowed to read 6  more  lines,  starting  with
       line one.

IOCTL FUNCTIONS

       Currently, there are two ioctl calls supported:

       IIOCGETDVR
              Get Revision information.
              Returns an unsigned long value v, representing various user level interface revisions, where

              (v & 0xff)
                     is the revision of the modem-register info, available via ioctl on /dev/isdnctrl.

              ((v >> 8) & 0xff)
                     is  the  revision  of  the net-interface config data, available via ioctl on /dev/isdnctrl.
                     and

              ((v >> 16) & 0xff)
                     is the revision of the data delivered via /dev/isdninfo itself.

       IIOCGETCPS
              Get transfer statistics.
              Returns the number of bytes transferred so far for  all  virtual  channels.  The  third  parameter
              should  be  a  pointer  to  an array of unsigned long of size ISDN_MAX_CHANNELS * 2. This array is
              filled with the byte counter values upon return.

OTHER CONSTANTS

       There are some more useful constants defined in /usr/include/linux/isdn.h:

       ISDN_TTY_MAJOR
              The major device number of /dev/ttyI.

       ISDN_TTYAUX_MAJOR
              The major device number of /dev/cui.

       ISDN_MAJOR
              The major device number of /dev/isdnctrl, /dev/isdninfo, /dev/ippp and /dev/isdn

       ISDN_MAX_DRIVERS
              The number of driver slots.

       ISDN_MAX_CHANNELS
              The number of virtual channels.

       ISDN_MINOR_CTRL
              The minor device number of /dev/isdnctrl0.

       ISDN_MINOR_CTRLMAX
              The minor device number of /dev/isdnctrl63.

       ISDN_MINOR_PPP
              The minor device number of /dev/ippp0.

       ISDN_MINOR_PPPMAX
              The minor device number of /dev/ippp64.

       ISDN_MINOR_STATUS
              The minor device number of /dev/isdninfo.

       Other constants, necessary for ioctl's on /dev/isdnctrl are listed in isdnctrl(4).

AUTHOR

       Fritz Elfert <fritz@isdn4linux.de>

SEE ALSO

       isdnctrl(4), icnctrl(4).