vidcontrol(1)

NAME

vidcontrol - system console control and configuration utili

ty

SYNOPSIS

vidcontrol  [-CdLHPpx] [-b color] [-c appearance] [-f [size]
file]
           [-g geometry] [-h size] [-i adapter |  mode]  [-l
screen_map]
           [-M   char]   [-m   on   |  off]  [-r  foreground
background]
           [-S on | off] [-s number] [-t N | off] [mode]
           [foreground [background]] [show]

DESCRIPTION

The vidcontrol command is used to set various options for

the syscons(4)
console driver, such as video mode, colors, cursor shape,

screen output
map, font and screen saver timeout.

The following command line options are supported:

mode Select a new video mode. The modes currently recog

nized are:

80x25, 80x30, 80x43, 80x50, 80x60, 132x25, 132x30,

132x43,
132x50, 132x60, VGA_40x25, VGA_80x25, VGA_80x30,

VGA_80x50,
VGA_80x60, VGA_90x25, VGA_90x30, VGA_90x43,

VGA_90x50, VGA_90x60,
EGA_80x25, EGA_80x43, VESA_132x25, VESA_132x43,

VESA_132x50,
VESA_132x60. The raster text mode VESA_800x600 can

also be chosen. Alternatively, a mode can be specified with

its number by
using a mode name of the form MODE_<NUMBER>. A list

of valid
mode numbers can be obtained with the -i mode op

tion. See Video
Mode Support below.

foreground [background]

Change colors when displaying text. Specify the

foreground color
(e.g. ``vidcontrol white''), or both a foreground

and background
colors (e.g. ``vidcontrol yellow blue''). Use the

show command
below to see available colors.

show See the supported colors on a given platform.

-b color

Set border color to color. This option may not be

always supported by the video driver.

-C Clear the history buffer.

-c normal | blink | destructive

Change the cursor appearance. The cursor is either

an inverting
block (normal) that can optionally blink, or it can

be like the
old hardware cursor (destructive). The latter is

actually a simulation.

-d Print out current output screen map.

-f [size] file

Load font file for size (currently, only 8x8, 8x14

or 8x16). The
font file can be either uuencoded or in raw binary

format. You
can also use the menu-driven vidfont(1) command to

load the font
of your choice.

Size may be omitted, in this case vidcontrol will

try to guess it
from the size of font file.

Note that older video cards, such as MDA and CGA, do

not support
software font. See also Video Mode Support and

EXAMPLES below
and the man page for syscons(4).

-g geometry

Set the geometry of the text mode for the modes with

selectable
geometry. Currently only raster modes, such as

VESA_800x600,
support this option. See also Video Mode Support

and EXAMPLES
below.

-h size

Set the size of the history (scrollback) buffer to

size lines.

-i adapter

Shows info about the current video adapter.

-i mode

Shows the possible video modes with the current

video hardware.

-l screen_map

Install screen output map file from screen_map. See

also
syscons(4).

-L Install default screen output map.

-M char

Sets the base character used to render the mouse

pointer to char.

-m on | off

Switch the mouse pointer on or off. Used together

with the
moused(8) daemon for text mode cut & paste function

ality.

-p Capture the current contents of the video buffer

corresponding to

the terminal device referred to by standard input.

The
vidcontrol utility writes contents of the video

buffer to the
standard output in a raw binary format. For details

about that
format see Format of Video Buffer Dump below.

-P Same as -p, but dump contents of the video buffer in

a plain text

format ignoring nonprintable characters and informa

tion about
text attributes.

-H When used with -p or -P, it instructs vidcontrol to

dump full

history buffer instead of visible portion of the

video buffer
only.

-r foreground background

Change reverse mode colors to foreground and

background.

-S on | off

Turn vty switching on or off. When vty switching is

off,
attempts to switch to a different virtual terminal

will fail.
(The default is to permit vty switching.) This pro

tection can be
easily bypassed when the kernel is compiled with the

DDB option.
However, you probably should not compile the kernel

debugger on a
box which is supposed to be physically secure.

-s number

Set the current vty to number.

-t N | off

Set the screensaver timeout to N seconds, or turns

it off.

-x Use hexadecimal digits for output.

Video Mode Support

Note that not all modes listed above may be supported by the

video hardware. You can verify which mode is supported by the video

hardware,
using the -i mode option.

The VESA BIOS support must be linked to the kernel or loaded

as a KLD
module if you wish to use VESA video modes or 132 column

modes (see
vga(4)).

You need to compile your kernel with the VGA_WIDTH90 option

if you wish
to use VGA 90 column modes (see vga(4)).

Video modes other than 25 and 30 line modes may require spe

cific size of
font. Use -f option above to load a font file to the ker

nel. If the
required size of font has not been loaded to the kernel,

vidcontrol will
fail if the user attempts to set a new video mode.

Modes Font size
25 line modes 8x16 (VGA), 8x14 (EGA)
30 line modes 8x16
43 line modes 8x8
50 line modes 8x8
60 line modes 8x8

It is better to always load all three sizes (8x8, 8x14 and

8x16) of the
same font.

You may set variables in /etc/rc.conf or /etc/rc.conf.local

so that
desired font files will be automatically loaded when the

system starts
up. See below.

If you want to use any of the raster text modes you need to

recompile
your kernel with the SC_PIXEL_MODE option. See syscons(4)

for more
details on this kernel option.

Format of Video Buffer Dump

The vidcontrol utility uses the syscons(4) CONS_SCRSHOT

ioctl(2) to capture the current contents of the video buffer. The

vidcontrol utility
writes version and additional information to the standard

output, followed by the contents of the terminal device.

VGA video memory is typically arranged in two byte tuples,

one per character position. In each tuple, the first byte will be the

character
code, and the second byte is the character's color at

tribute.

The VGA color attribute byte looks like this:

bits# width meaning
7 <X0000000> 1 character blinking
6:4 <0XXX0000> 3 background color
3 <0000X000> 1 bright foreground color
2:0 <00000XXX> 3 foreground color

Here is a list of the three bit wide base colors:

0 Black
1 Blue
2 Green
3 Cyan
4 Red
5 Magenta
6 Brown
7 Light Grey

Base colors with bit 3 (the bright foreground flag) set:

0 Dark Grey
1 Light Blue
2 Light Green
3 Light Cyan
4 Light Red
5 Light Magenta
6 Yellow
7 White

For example, the two bytes

65 158

specify an uppercase A (character code 65), blinking (bit 7

set) in yellow (bits 3:0) on a blue background (bits 6:4).

The vidcontrol output contains a small header which includes

additional
information which may be useful to utilities processing the

output.

The first 10 bytes are always arranged as follows:

Byte Range Contents
1 thru 8 Literal text ``SCRSHOT_''
9 File format version number
10 Remaining number of bytes in the header

Subsequent bytes depend on the version number.

Version Byte Meaning 1 11 Terminal width, in characters

12 Terminal depth, in characters
13 and up The snapshot data

So a dump of an 80x25 screen would start (in hex)

53 43 52 53 48 4f 54 5f 01 02 50 19
----------------------- -- -- -- -

| | | | ` 25 decimal
| | | `--- 80 decimal
| | `------ 2 remaining bytes

of header data
| `--------- File format ver

sion 1
`------------------------ Literal "SCRSHOT_"

VIDEO OUTPUT CONFIGURATION

Boot Time Configuration

You may set the following variables in /etc/rc.conf or

/etc/rc.conf.local
in order to configure the video output at boot time.

blanktime Sets the timeout value for the -t option. font8x16, font8x14, font8x8

Specifies font files for the -f option.

scrnmap Specifies a screen output map file for the -l

option.

See rc.conf(5) for more details.

Driver Configuration

The video card driver may let you change default configura

tion options,
such as the default font, so that you do not need to set up

the options
at boot time. See video card driver manuals, (e.g. vga(4))

for details.

FILES

/usr/share/syscons/fonts/* font files.
/usr/share/syscons/scrnmaps/* screen output map

files.

EXAMPLES

If you want to load /usr/share/syscons/fonts/iso-8x16.fnt to

the kernel,
run vidcontrol as:

vidcontrol -f 8x16

/usr/share/syscons/fonts/iso-8x16.fnt

So long as the font file is in /usr/share/syscons/fonts, you

may abbreviate the file name as iso-8x16:

vidcontrol -f 8x16 iso-8x16

Furthermore, you can also omit font size ``8x16'':

vidcontrol -f iso-8x16

Moreover, the suffix specifying the font size can be also

omitted; in
this case, vidcontrol will use the size of the currently

displayed font
to construct the suffix:

vidcontrol -f iso

Likewise, you can also abbreviate the screen output map file

name for the
-l option if the file is found in

/usr/share/syscons/scrnmaps.

vidcontrol -l iso-8859-1_to_cp437

The above command will load
/usr/share/syscons/scrnmaps/iso-8859-1_to_cp437.scm.

The following command will set-up a 100x37 raster text mode

(useful for
some LCD models):

vidcontrol -g 100x37 VESA_800x600

The following command will capture the contents of the first

virtual terminal, and redirect the output to the shot.scr file:

vidcontrol -p < /dev/ttyv0 > shot.scr

The following command will dump contents of the fourth vir

tual terminal
to the standard output in the human readable format:

vidcontrol -P < /dev/ttyv3

SEE ALSO

kbdcontrol(1), vidfont(1), keyboard(4), screen(4),

syscons(4), vga(4),
rc.conf(5), kldload(8), moused(8), watch(8)

The various scr2* utilities in the graphics and textproc

categories of
the Ports Collection.

AUTHORS

Soren Schmidt <sos@FreeBSD.org>
Sascha Wildner

CONTRIBUTORS

Maxim Sobolev <sobomax@FreeBSD.org>, Nik Clayton <nik@FreeB

SD.org>

BSD May 29, 2005

BSD