syscons(4)

NAME

syscons, sc - the console driver

SYNOPSIS

options MAXCONS=N
options SC_ALT_MOUSE_IMAGE
options SC_CUT_SEPCHARS=_characters_
options SC_CUT_SPACES2TABS
options SC_DISABLE_KDBKEY
options SC_DISABLE_REBOOT
options SC_HISTORY_SIZE=N
options SC_MOUSE_CHAR=C
options SC_NO_CUTPASTE
options SC_NO_FONT_LOADING
options SC_NO_HISTORY
options SC_NO_PALETTE_LOADING
options SC_NO_SUSPEND_VTYSWITCH
options SC_NO_SYSMOUSE
options SC_PIXEL_MODE
options SC_TWOBUTTON_MOUSE
options SC_NORM_ATTR=_attribute_
options SC_NORM_REV_ATTR=_attribute_
options SC_KERNEL_CONS_ATTR=_attribute_
options SC_KERNEL_CONS_REV_ATTR=_attribute_
options SC_DFLT_FONT
makeoptions SC_DFLT_FONT=_font_name_
device sc
In /boot/device.hints:
hint.sc.0.at="isa"

DESCRIPTION

The syscons driver provides multiple virtual terminals. It

resembles the
SCO color console driver.

The syscons driver is implemented on top of the keyboard

driver
(atkbd(4)) and the video card driver (vga(4)) and so re

quires both of
them to be configured in the system.

There can be only one syscons device defined in the system.

Virtual Terminals

The syscons driver provides multiple virtual terminals which

appear as if
they were separate terminals. One virtual terminal is con

sidered current
and exclusively occupies the screen and the keyboard; the

other virtual
terminals are placed in the background.

In order to use virtual terminals, they must be individually

marked
``on'' in /etc/ttys so that getty(8) will recognize them to

be active and
run login(1) to let the user log in to the system. By de

fault, only the
first eight virtual terminals are activated in /etc/ttys.

You press the Alt key and a switch key to switch between

virtual terminals. The following table summarizes the correspondence be

tween the
switch key and the virtual terminal.

Alt-F1 ttyv0 Alt-F7 ttyv6 Shift-Alt-F1

ttyv10
Alt-F2 ttyv1 Alt-F8 ttyv7 Shift-Alt-F2

ttyv11
Alt-F3 ttyv2 Alt-F9 ttyv8 Shift-Alt-F3

ttyv12
Alt-F4 ttyv3 Alt-F10 ttyv9 Shift-Alt-F4

ttyv13
Alt-F5 ttyv4 Alt-F11 ttyv10 Shift-Alt-F5

ttyv14
Alt-F6 ttyv5 Alt-F12 ttyv11 Shift-Alt-F6

ttyv15

You can also use the ``nscr'' key (usually the PrintScreen

key on the AT
Enhanced keyboard) to cycle available virtual terminals.

The default number of available virtual terminals is 16.

This can be
changed with the kernel configuration option MAXCONS (see

below).

Note that the X server usually requires a virtual terminal

for display
purposes, so at least one terminal must be left unused by

getty(8) so
that it can be used by the X server.

Key Definitions and Function Key Strings

The syscons driver, in conjunction with the keyboard driver,

allows the
user to change key definitions and function key strings.

The
kbdcontrol(1) command will load a key definition file (known

as
``keymap'' file), dump the current keymap, and assign a

string to a function key. See keyboard(4) and kbdmap(5) for the keymap

file.

You may want to set the keymap variable in

/etc/rc.conf.local to the
desired keymap file so that it will be automatically loaded

when the system starts up.

Software Font

For most modern video cards, e.g., VGA, the syscons driver

and the video
card driver allow the user to change the font used on the

screen. The
vidcontrol(1) command can be used to load a font file from
/usr/share/syscons/fonts.

The font comes in various sizes: 8x8, 8x14 and 8x16. The

8x16 font is
typically used for the VGA card in the 80-column-by-25-line

mode. Other
video modes may require different font sizes. It is better

to always
load all three sizes of the same font.

You may set font8x8, font8x14 and font8x16 variables in

/etc/rc.conf to
the desired font files so that they will be automatically

loaded when the
system starts up.

Optionally you can specify a particular font file as the de

fault. See
the SC_DFLT_FONT option below.

Screen Map

If your video card does not support software fonts, you may

still be able
to achieve a similar effect by re-mapping the font built in

to your video
card. Use vidcontrol(1) to load a screen map file which de

fines the mapping between character codes.

Mouse Support and Copy-and-Paste

You can use your mouse to copy text on the screen and paste

it as if it
was typed by hand. You must be running the mouse daemon

moused(8) and
enable the mouse cursor in the virtual terminal via vidcon

trol(1).

Pressing mouse button 1 (usually the left button) will start

selection.
Releasing button 1 will end the selection process. The se

lected text
will be marked by inverting foreground and background col

ors. You can
press button 3 (usually the right button) to extend the se

lected region.
The selected text is placed in the copy buffer and can be

pasted at the
cursor position by pressing button 2 (usually the middle

button) as many
times as you like.

If your mouse has only two buttons, you may want to use the
SC_TWOBUTTON_MOUSE option below to make the right button to

paste the
text. Alternatively you can make the mouse daemon emulate

the middle
button. See the man page for moused(8) for more details.

Back Scrolling

The syscons driver allows the user to browse the output

which has
``scrolled off'' the top of the screen.

Press the ``slock'' key (usually ScrllLock / Scroll Lock or

Pause on many
keyboards) and the terminal is in the ``scrollback'' mode.

It is indicated by the Scroll Lock LED. Use the arrow keys, the Page

Up/Down keys
and the Home/End keys to scroll buffered terminal output.

Press the
``slock'' key again to get back to the normal terminal mode.

The size of the scrollback buffer can be set by the SC_HIS

TORY_SIZE
option described below.

Screen Saver

The syscons driver can be made to put up the screen saver if

the current
virtual terminal is idle, that is, the user is not typing on

the keyboard
nor moving the mouse. See splash(4) and vidcontrol(1) for

more details.

DRIVER CONFIGURATION

Kernel Configuration Options

The following kernel configuration options control the

syscons driver.

MAXCONS=N

This option sets the number of virtual terminals to

N. The
default value is 16.

SC_ALT_MOUSE_IMAGE

This option selects the alternative way of displaying

the mouse
cursor in the virtual terminal. It may be expensive

for some
video cards to draw the arrow-shaped cursor, and you

may want to
try this option. However, the appearance of the al

ternative mouse
cursor may not be very appealing. Note that if you

use the
SC_NO_FONT_LOADING option then you must also use this

option if
you wish to be able to use the mouse.

SC_CUT_SEPCHARS=_characters_

This options specifies characters that will be looked

for when the
driver searches for words boundaries when doing cut

operation. By
default, its value is "0" -- a space character.

SC_CUT_SPACES2TABS

This options instructs the driver to convert leading

spaces into
tabs when copying data into cut buffer. This might

be useful to
preserve indentation when copying tab-indented text.

SC_DISABLE_KDBKEY

This option disables the ``debug'' key combination

(by default, it
is Alt-Esc, or Ctl-PrintScreen). It will prevent

users from
entering the kernel debugger (KDB) by pressing the

key combination. KDB will still be invoked when the kernel pan

ics or hits a
break point if it is included in the kernel. If this

option is
not defined, this behavior may be controled at run

time by the
sysctl(8) variable (hw.syscons.kbd_kbdkey).

SC_DISABLE_REBOOT

This option disables the ``reboot'' key (by default,

it is
Ctl-Alt-Del), so that the casual user may not acci

dentally reboot
the system. If this option is not defined, this be

havior may be
controled at runtime by the sysctl(8) variable
(hw.syscons.kbd_reboot).

SC_HISTORY_SIZE=N

Sets the size of back scroll buffer to N lines. The

default value
is 100.

SC_MOUSE_CHAR=C

Unless the SC_ALT_MOUSE_IMAGE option above is speci

fied, the
syscons driver reserves four consecutive character

codes in order
to display the mouse cursor in the virtual terminals

in some systems. This option specifies the first character code

to C to be
used for this purpose. The default value is 0xd0. A

good candidate is 0x03.

SC_PIXEL_MODE

Adds support for pixel (raster) mode console. This

mode is useful
on some laptop computers, but less so on most other

systems, and
it adds substantial amount of code to syscons. If

this option is
NOT defined, you can reduce the kernel size a lot.

See the
VESA800X600 flag below.

SC_TWOBUTTON_MOUSE

If you have a two button mouse, you may want to add

this option to
use the right button of the mouse to paste text. See

Mouse
Support and Copy-and-Paste above.

SC_NORM_ATTR=_attribute_

SC_NORM_REV_ATTR=_attribute_

SC_KERNEL_CONS_ATTR=_attribute_

SC_KERNEL_CONS_REV_ATTR=_attribute_

These options will set the default colors. Available

colors are
defined in See EXAMPLES below.

SC_DFLT_FONT

This option will specify the default font. Available

fonts are:
iso, iso2, koi8-r, koi8-u, cp437, cp850, cp865, cp866

and cp866u.
16-line, 14-line and 8-line font data will be com

piled in. Without this option, the syscons driver will use whatever

font is
already loaded in the video card, unless you explic

itly load a
software font at startup. See EXAMPLES below.

SC_NO_SUSPEND_VTYSWITCH

This option, which is also available as loader(8)

tunable and
sysctl(8) variable

(hw.syscons.sc_no_suspend_vtswitch), disables switching between virtual terminals (graphics <->

text) during
suspend/resume (ACPI and APM). Use this option if

your system is
freezing when you are running X and trying to sus

pend.

The following options will remove some features from the

syscons driver
and save kernel memory.

SC_NO_CUTPASTE

This option disables ``copy and paste'' operation in

virtual terminals.

SC_NO_FONT_LOADING

The syscons driver can load software fonts on some

video cards.
This option removes this feature. Note that if you

still wish to
use the mouse with this option then you must also use

the
SC_ALT_MOUSE_IMAGE option.

SC_NO_HISTORY

This option disables back-scrolling in virtual termi

nals.

SC_NO_SYSMOUSE

This option removes mouse support in the syscons

driver. The
mouse daemon moused(8) will fail if this option is

defined. This
option implies the SC_NO_CUTPASTE option too.

Driver Flags

The following driver flags can be used to control the

syscons driver.
They can be set either in /boot/device.hints, or else at the

loader
prompt (see loader(8)).

0x0080 (VESA800X600)

This option puts the video card in the VESA 800x600

pixel, 16
color mode. It may be useful for laptop computers

for which the
800x600 mode is otherwise unsupported by the X serv

er. Note that
in order for this flag to work, the kernel must be

compiled with
the SC_PIXEL_MODE option explained above.

0x0100 (AUTODETECT_KBD)

This option instructs the syscons driver to periodi

cally scan for
a keyboard device if it is not currently attached to

one. Otherwise, the driver only probes for a keyboard once dur

ing bootup.

FILES

/dev/console
/dev/consolectl
/dev/ttyv? virtual terminals
/etc/ttys terminal initialization in

formation
/usr/share/syscons/fonts/* font files
/usr/share/syscons/keymaps/* key map files
/usr/share/syscons/scrmaps/* screen map files

EXAMPLES

As the syscons driver requires the keyboard driver and the

video card
driver, the kernel configuration file should contain the

following lines.

device atkbdc
device atkbd
device vga
device sc

device splash

You also need the following lines in /boot/device.hints for

these
drivers.

hint.atkbdc.0.at="isa"
hint.atkbdc.0.port="0x060"
hint.atkbd.0.at="atkbdc"
hint.atkbd.0.irq="1"
hint.vga.0.at="isa"
hint.sc.0.at="isa"

If you do not intend to load the splash image or use the

screen saver,
the last line is not necessary, and can be omitted.

Note that the keyboard controller driver atkbdc is required

by the keyboard driver atkbd.

The following lines will set the default colors. The normal

text will be
green on black background. The reversed text will be yellow

on green
background. Note that you cannot put any white space inside

the quoted
string, because of the current implementation of config(8).

options SC_NORM_ATTR=(FG_GREEN|BG_BLACK)
options SC_NORM_REV_ATTR=(FG_YELLOW|BG_GREEN)

The following lines will set the default colors of the ker

nel message.
The kernel message will be printed bright red on black back

ground. The
reversed message will be black on red background.

options SC_KERNEL_CONS_ATTR=(FG_LIGHTRED|BG_BLACK)
options SC_KERNEL_CONS_REV_ATTR=(FG_BLACK|BG_RED)

The following example adds the font files cp850-8x16.fnt,

cp850-8x14.font
and cp850-8x8.font to the kernel.

options SC_DFLT_FONT
makeoptions SC_DFLT_FONT=cp850
device sc

CAVEATS

The amount of data that is possible to insert from the cut

buffer is limited by the {MAX_INPUT}, a system limit on the number of

bytes that may
be stored in the terminal input queue - usually 1024 bytes

(see
termios(4)).

SEE ALSO

kbdcontrol(1), login(1), vidcontrol(1), atkbd(4), atkbdc(4),

keyboard(4),
screen(4), splash(4), ukbd(4), vga(4), kbdmap(5),

rc.conf(5), ttys(5),
config(8), getty(8), kldload(8), moused(8)

HISTORY

The syscons driver first appeared in FreeBSD 1.0.

AUTHORS

The syscons driver was written by Soren Schmidt <sos@FreeB

SD.org>. This
manual page was written by Kazutaka Yokota <yokota@FreeB

SD.org>.

BUGS

This manual page is incomplete and urgently needs revision.

BSD June 30, 1999

BSD