conscontrol
—
control physical console devices
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
.
The conscontrol
utility first appeared in
FreeBSD 5.0.