conscontrol(8)

NAME

conscontrol - control physical console devices

SYNOPSIS

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

DESCRIPTION

The conscontrol utility is used to examine and modify the

physical
devices which back the virtual console devices. If no argu

ments (or only
the list command) are specified, the current console set

tings are shown.

There are two types of logical consoles; a high level con

sole 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 sup

port, while the
high level console is used by user programs like syslogd(8).

Multiple
device support is implemented only for the low level con

sole; the high
level console is set to the first device in the console

list.

Multiple console support may be invoked by passing the ker

nel 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 console | unset

Set or unset the virtual console. When unset, out

put 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.

SEE ALSO

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

HISTORY

The conscontrol utility first appeared in FreeBSD 5.0.

AUTHORS

Jonathan Lemon

BSD October 23, 2001

BSD