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CONSOLEFS(4)               Kernel Interfaces Manual               CONSOLEFS(4)



NAME
       consolefs, C  - file system for console access

SYNOPSIS
       aux/consolefs name dev [ name dev ...  ]

       C system

DESCRIPTION
       To  ease  administration  of  multiple  machines  one might attach many
       serial console lines to a single computer.  Consolefs is a file  system
       that  lets  multiple  users  simultaneously access these console lines.
       Each name/dev pair represents the name of a console and the serial line
       device associated with it.  Consolefs presents a single level directory
       with two files per console: name  and  namectl.   Writes  of  name  are
       equivalent to writes of dev and reads and writes of namectl are equiva-
       lent to reads and writes of devctl.  Consolefs broadcasts  anything  it
       reads  from  dev  to  all  readers  of name.  Therefore, many users can
       con(1) to a name, see all console output, and  enter  commands  to  the
       console.

       To  keep users from inadvertently interfering with one another, notifi-
       cation is broadcast to all readers whenever  a  user  opens  or  closes
       name.   For  example, if user boris opens a console that users vlad and
       barney have already opened, all will read the message:

            [+boris, vlad, barney]

       If vlad then closes, boris and barney will read:

            [-vlad, boris, barney]

       Consolefs posts the client end of its  9P  channel  in  /srv/consolefs;
       mount  (see  bind(1))  this  file to see the consoles.  An example of 2
       consoles complete with console logging is:

              % aux/consolefs bootes /dev/eia0 fornax /dev/eia1
              % mount /srv/consoles /mnt/consoles
              % ls -p /mnt/consoles
              bootes
              bootesctl
              fornax
              fornaxctl
              % cat /mnt/consoles/fornax >> /sys/log/fornax &
              % cat /mnt/consoles/bootes >> /sys/log/bootes &

       The rc(1) script C automates this procedure.  It uses import(4) to con-
       nect  to  /mnt/consoles  on  the machine connected to all the consoles,
       then uses con(1) to connect to the console of the machine system.   The
       script  must  be  edited at installation by the local administration to
       identify the system that holds /mnt/consoles.

FILES
       /srv/consoles
              Client end of pipe to server.

SOURCE
       /sys/src/cmd/aux/consolefs.l
       /rc/bin/C



                                                                  CONSOLEFS(4)