NAME
vidcontrol
—
system console control and
configuration utility
SYNOPSIS
vidcontrol |
[-CdLHPpx ] [-b
color] [-c
appearance] [-f
[[size] file]]
[-g geometry]
[-h size]
[-i active |
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) or vt(4) console driver, such as video mode, colors, cursor
shape, screen output map, font and screen saver timeout. Only a small subset
of options is supported by
vt(4). Unsupported options lead to error messages, typically
including the text "Inappropriate ioctl for device".
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
setting[,setting ...]- Change the cursor appearance. The change is specified by a non-empty
comma-separated list of
setting
s. Eachsetting
overrides or modifies previous ones in left to right order.The following override
setting
s are available:normal
- Set to a block covering 1 character cell, with a configuration-dependent coloring that should be at worst inverse video.
destructive
- Set to a blinking sub-block with
height
scanlines starting atbase
. The name “destructive” is bad for backwards compatibility. Thissetting
should not force destructiveness, and it now only gives destructiveness in some configurations (typically for hardware cursors in text mode). Blinking limits destructiveness. Thissetting
should now be spellednormal
,blink
,noblock
. A non-blinking destructive cursor would be unusable, so old versions ofvidcontrol
didn't support it, and this version doesn't have an override for it. base
=value,height
=value- Set the specified scanline parameters. These parameters are only
active in
noblock
mode.value
is an integer in any base supported by strtol(3). Settingheight
to 0 turns off the cursor innoblock
mode. Negative values are silently ignored. Positive values are clamped to fit in the character cell when the cursor is drawn.
The following modifier
setting
s are available:blink
,noblink
- Set or clear the blinking attribute. This is not quite backwards
compatible. In old versions of
vidcontrol
,blink
was an override to a blinking block. block
,noblock
- Set or clear the
block
attribute. This attribute is the inverse of the flagCONS_CHAR_CURSOR
in the implementation. It deactivates the scanline parameters, and expresses a preference for using a simpler method of implementation. Its inverse does the opposite. When the scanline parameters give a full block, this attribute reduces to a method selection bit. Theblock
method tends to give better coloring. - Set or clear the hidden attribute.
The following (non-sticky) flags control application of the
setting
s:charcolors
- Apply
base
andheight
to the (character) cursor's list of preferred colors instead of its shape. Beware that the color numbers are raw VGA palette indexes, not ANSI color numbers. The indexes are reduced mod 8, 16 or 256, or ignored, depending on the video mode and renderer. mousecolors
- Colors for the mouse cursor in graphics mode. Like
charcolors
, except there is no preference or sequence;base
gives the mouse border color andheight
gives the mouse interior color. Together withcharcolors
, this gives 2 selection bits which select between only 3 of 4 sub-destinations of the 4 destinations selected bydefault
andlocal
(by ignoringmousecolors
ifcharcolors
is also set). default
- Apply the changes to the default settings and then to the active
settings, instead of only to the active settings. Together with
local
, this gives 2 selection bits which select between 4 destinations. shapeonly
- Ignore any changes to the
block
andhidden
attributes. local
- Apply the changes to the current vty. The default is to apply them to a global place and copy from there to all vtys.
reset
- Reset everything. The default is to not reset. When the
local
parameter is specified, the current local settings are reset to default local settings. Otherwise, the current global settings are reset to default global settings and then copied to the current and default settings for all vtys. show
- Show the current changes.
-d
- Print out current output screen map.
-f
[[size] file]- Load font file for size
(currently, only
8x8
,8x14
or8x16
). 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.When using vt(4) both size and font can be omitted, and the default font will be loaded.
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 either syscons(4) or vt(4) (depending on which driver you use).
-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
active
- Shows the active vty number.
-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) or vt(4) (depending on which driver you use).
-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
oroff
. 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 instructsvidcontrol
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 active 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) or
vt(4)
(depending on which driver you use) for more details on this kernel
option.
Format of Video Buffer Dump
The vidcontrol
utility uses the
syscons(4) or vt(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.
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/*
- /usr/share/vt/fonts/*
- font files.
- /usr/share/syscons/scrnmaps/*
- screen output map files (relevant for syscons(4) only).
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 (if using syscons) or /usr/share/vt/fonts (if using vt), 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), vt(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
<saw@online.de>
CONTRIBUTORS
Maxim Sobolev
<sobomax@FreeBSD.org>
Nik Clayton
<nik@FreeBSD.org>