The
driver provides multiple virtual terminals.
It resembles the SCO color console driver.
The
driver is implemented on top of the keyboard driver
(atkbd(4)
)
and the video card driver
(vga(4)
)
and so requires both of them to be configured in the system.
There can be only one
device defined in the system.
Virtual Terminals
The
driver provides multiple virtual terminals which appear as if they were
separate terminals.
One virtual terminal is considered 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 default, 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 between the switch
key and the virtual terminal.
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
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
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
font8x8font8x14
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 default.
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 into your video card.
Use
vidcontrol(1)
to load a screen map file which defines 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
vidcontrol(1).
Pressing mouse button 1 (usually the left button) will start selection.
Releasing button 1 will end the selection process.
The selected text will be marked by inverting foreground and
background colors.
You can press button 3 (usually the right button) to extend
the selected 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
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_HISTORY_SIZE
option described below.
Screen Saver
The
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
driver.
MAXCONS=N
This option sets the number of virtual terminals to
Fa 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 alternative 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
Qq Li \x20
--- 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 panics or hits a break point
if it is included in the kernel.
If this option is not defined, this behavior may be controlled at runtime
by the
sysctl(8)
variable
hw.syscons.kbd_debug
SC_DISABLE_REBOOT
This option disables the ``reboot'' key (by default, it is
Ctl-Alt-Del )
so that the casual user may not accidentally reboot the system.
If this option is not defined, this behavior may be controlled at runtime
by the
sysctl(8)
variable
hw.syscons.kbd_reboot
SC_HISTORY_SIZE=N
Sets the size of back scroll buffer to
Fa N
lines.
The default value is 100.
SC_MOUSE_CHAR=C
Unless the
SC_ALT_MOUSE_IMAGE
option above is specified, the
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
Fa 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
Sx 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
In machine/pc/display.h .
See
Sx 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 compiled in.
Without this option, the
driver will use whatever font is already loaded in the video card,
unless you explicitly load a software font at startup.
See
Sx 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 suspend.
The following options will remove some features from the
driver and save kernel memory.
SC_NO_CUTPASTE
This option disables ``copy and paste'' operation in virtual
terminals.
SC_NO_FONT_LOADING
The
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 terminals.
SC_NO_SYSMOUSE
This option removes mouse support in the
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
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 server.
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 periodically scan
for a keyboard device if it is not currently attached to one.
Otherwise, the driver only probes for a keyboard once during bootup.
FILES
/dev/console
/dev/consolectl
/dev/ttyv?
virtual terminals
/etc/ttys
terminal initialization information
/usr/share/syscons/fonts/*
font files
/usr/share/syscons/keymaps/*
key map files
/usr/share/syscons/scrmaps/*
screen map files
EXAMPLES
As the
driver requires the keyboard driver and the video card driver,
the kernel configuration file should contain the following lines.
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 kernel message.
The kernel message will be printed bright red on black background.
The reversed message will be black on red background.
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
Br q Dv 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)).
An -nosplit
The
driver was written by
An S/oren Schmidt Aq [email protected] .
This manual page was written by
An Kazutaka Yokota Aq [email protected] .
BUGS
This manual page is incomplete and urgently needs revision.