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CONSCONTROL(8)          FreeBSD System Manager's Manual         CONSCONTROL(8)

     conscontrol - control physical console devices

     conscontrol [list]
     conscontrol mute on | off
     conscontrol add | delete console
     conscontrol set | unset console

     The conscontrol utility is used to examine and modify the physical
     devices which back the virtual console devices.  If no arguments (or only
     the list command) are specified, the current console settings are shown.

     There are two types of logical consoles; a high level console which is
     represented by /dev/console, and a low level console.  The low level
     console is used for kernel printf(9) and ddb(4) debugger support, while
     the high level console is used by user programs like syslogd(8).
     Multiple device support is implemented only for the low level console;
     the high level console is set to the first device in the console list.

     Multiple console support may be invoked by passing the kernel the -D flag
     from the boot loader, or by using conscontrol to change the list of
     console devices after the system has booted.

     The following options are available:

     add | delete console
             Add or delete a physical device from the logical console.  The
             device must support low-level console operations.  Adding a
             device will place it at the front of the list of console devices;
             the first device is used for the high level console.

             The console argument is the name of a console device in /dev; the
             name of the directory may be omitted.

     mute on | off
             Change the state of console muting.  All console output is
             suppressed when console muting is on.

     set | unset console
             Set or unset the virtual console.  When unset, output from the
             system, such as the kernel printf(9), always goes out to the real
             main console.  When set, it goes to another.  This is an
             interface to the tty ioctl TIOCCONS.

     sio(4), syscons(4), tty(4), boot(8), loader(8)

     The conscontrol utility first appeared in FreeBSD 5.0.

     Jonathan Lemon

FreeBSD 11.0-PRERELEASE         April 14, 2011         FreeBSD 11.0-PRERELEASE


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