NAME¶
vidcontrol —
system console control and
configuration utility
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 xterm |
cons25] [-t
N | off]
[mode]
[foreground
[background]]
[show] |
DESCRIPTION¶
The
vidcontrol utility 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 recognized
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 option. 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 functionality.
- -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
information 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 protection 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
xterm | cons25
- Switch between xterm and cons25 style terminal
emulation.
- -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 specific size of font.
Use
-f option above to load a font file to the kernel. 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.
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 video buffer.
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 attribute.
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.
| Sy 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 version 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 configuration 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
video buffer, and redirect the output to the
shot.scr file:
vidcontrol -p < /dev/ttyv0 >
shot.scr
The following command will dump contents of the fourth virtual terminal video
buffer 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¶
Søren Schmidt ⟨sos@FreeBSD.org⟩
Sascha Wildner
CONTRIBUTORS¶
Maxim Sobolev ⟨sobomax@FreeBSD.org⟩,
Nik Clayton ⟨nik@FreeBSD.org⟩
