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VIDCONTROL(1)           FreeBSD General Commands Manual          VIDCONTROL(1)

     vidcontrol - system console control and configuration utility

     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]

     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 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

     -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.

             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

     -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) 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 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

     -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

     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

   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.

           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_"

   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.

     /usr/share/vt/fonts/*                font files.
     /usr/share/syscons/scrnmaps/*        screen output map files (relevant
                                          for syscons(4) only).

     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

     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

     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.

     Soren Schmidt <>
     Sascha Wildner

     Maxim Sobolev <>,
     Nik Clayton <>

FreeBSD 11.0-PRERELEASE        December 23, 2006       FreeBSD 11.0-PRERELEASE


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