freebsd/share/man/man4/vt.4

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.Dd July 2, 2014
.Dt "VIRTUAL TERMINALS" 4
.Os
.Sh NAME
.Nm vt
.Nd virtual terminal console driver
.Sh SYNOPSIS
.Cd "options TERMINAL_KERN_ATTR=_attribute_"
.Cd "options TERMINAL_NORM_ATTR=_attribute_"
.Cd "options VT_MAXWINDOWS=N"
.Cd "options VT_ALT_TO_ESC_HACK=1"
.Cd "options VT_TWOBUTTON_MOUSE"
.Cd "options VT_FB_DEFAULT_WIDTH=X"
.Cd "options VT_FB_DEFAULT_HEIGHT=Y"
.Cd "options SC_NO_CUTPASTE"
.Cd "device vt"
.Pp
In
.Xr loader.conf 5 :
.Cd hw.vga.textmode=1
.Cd kern.vty=vt
.Cd kern.vt.spclkeys=15
.Sh DESCRIPTION
The
.Nm
device provides multiple virtual terminals with an extensive feature
set:
.Bl -item -offset indent
.It
Unicode UTF-8 text with double-width characters.
.It
Large font maps in graphics mode, including support for Asian
character sets.
.It
Graphics-mode consoles.
.It
Integration with
KMS
.Pq Kernel Mode Setting
video drivers for switching between the
.Em X Window System
and virtual terminals.
.El
.Ss Virtual Terminals
Multiple virtual terminals are provided on a single computer.
Up to sixteen virtual terminals can be defined.
A single virtual terminal is connected to the screen and keyboard
at a time.
Key combinations are used to select a virtual terminal.
Alt-F1 through Alt-F12 correspond to the first twelve virtual terminals.
If more than twelve virtual terminals are created, Shift-Alt-F1 through
Shift-Alt-F4 are used to switch to the additional terminals.
.Ss Copying and Pasting Text with a Mouse
Copying and pasting text from the screen with a mouse is supported.
Press and hold down mouse button 1, usually the left button, while
moving the mouse to select text.
Selected text is highlighted with reversed foreground and background
colors.
To select more text after releasing mouse button 1, press mouse button
3, usually the right button.
To paste text that has been selected, press mouse button 2, usually the
middle button.
The text is entered as if it were typed at the keyboard.
The
.Dv VT_TWOBUTTON_MOUSE
kernel option can be used with mice that only have two buttons.
Setting this option makes the second mouse button into the
paste button.
See
.Xr moused 8
for more information.
.Ss Scrolling Back
Output that has scrolled off the screen can be reviewed by pressing the
Scroll Lock key, then scrolling up and down with the arrow keys.
The Page Up and Page Down keys scroll up or down a full screen at a
time.
The Home and End keys jump to the beginning or end of the scrollback
buffer.
When finished reviewing, press the Scroll Lock key again to return to
normal use.
.Sh DRIVER CONFIGURATION
.Ss Kernel Configuration Options
These kernel options control the
.Nm
driver.
.Bl -tag -width MAXCONS
.It Dv TERMINAL_NORM_ATTR= Ns Pa attribute
.It Dv TERMINAL_KERN_ATTR= Ns Pa attribute
These options allow changing the default colors used for normal and kernel
text.
Available colors are defined in
.In sys/terminal.h .
See
.Sx EXAMPLES
below.
.It Dv VT_MAXWINDOWS=N
Set the number of virtual terminals to be created to
.Fa N .
The value defaults to 12.
.It Dv VT_ALT_TO_ESC_HACK=1
When the Alt key is held down while pressing another key, send an ESC
sequence instead of the Alt key.
.It Dv VT_TWOBUTTON_MOUSE
If defined, swap the functions of mouse buttons 2 and 3.
In effect, this makes the right-hand mouse button perform a paste.
These options are checked in the order shown.
.It Dv SC_NO_CUTPASTE
Disable mouse support.
.It VT_FB_DEFAULT_WIDTH=X
Set the default width to
.Fa X .
.It VT_FB_DEFAULT_HEIGHT=Y
Set the default height to
.Fa Y .
.El
.Sh BACKWARDS COMPATIBILITY
Several options are provided for compatibility with the previous
console device,
.Xr sc 4 .
These options will be removed in a future
.Fx
version.
.Bl -column -offset indent ".Sy vt VT_TWOBUTTON_MOUSE" ".Sy SC_TWOBUTTON_MOUSE"
.It Sy vt Option Name Ta Sy sc Option Name
.It Dv TERMINAL_KERN_ATTR Ta Dv SC_KERNEL_CONS_ATTR
.It Dv TERMINAL_NORM_ATTR Ta Dv SC_NORM_ATTR
.It Dv VT_TWOBUTTON_MOUSE Ta Dv SC_TWOBUTTON_MOUSE
.It Dv VT_MAXWINDOWS Ta Dv MAXCONS
.It none Ta Dv SC_NO_CUTPASTE
.El
.Sh START-UP OPERATION WITH X86 BIOS SYSTEMS
The computer BIOS starts in text mode, and
the
.Fx
.Xr loader 8
runs, loading the kernel.
If
.Va hw.vga.textmode
is set, the system remains in text mode.
Otherwise,
.Nm
switches to 640x480x16 VGA mode using
.Cm vt_vga .
If a KMS
.Pq Kernel Mode Switching
video driver is available, the display is switched to high resolution
and the KMS driver takes over.
When a KMS driver is not available,
.Cm vt_vga
remains active.
.Sh LOADER TUNABLES
These settings can be entered at the
.Xr loader 8
prompt or in
.Xr loader.conf 5 .
.Bl -tag -width indent
.It Va hw.vga.textmode
Set to 1 to use virtual terminals in text mode instead of graphics mode.
Features that require graphics mode, like loadable fonts, will be
disabled.
.It Va kern.vty
When both
.Nm
and
.Xr sc 4 have been compiled into the kernel, the one to use for the
system console can be selected by setting this value to
.Ql vt
or
.Ql sc .
If this value is not set,
.Xr sc 4
is used.
.It Va kern.vt.spclkeys
bitmap of allowed special keys. 1 is enabled, 0 is disabled. Encoded as:
.Bl -tag -compact -width 0x000000
.It 0x0001
Debug request key combination. (Ctrl+Alt+Esc)
.It 0x0002
Reboot. (Ctrl+Alt+Del)
.It 0x0004
Halt.
.It 0x0008
Power down.
.El
Default is 15, all enabled.
.El
.Sh FILES
.Bl -tag -width /usr/share/syscons/keymaps/* -compact
.It Pa /dev/console
.It Pa /dev/consolectl
.It Pa /dev/ttyv*
virtual terminals
.It Pa /etc/ttys
terminal initialization information
.El
.Sh EXAMPLES
This example changes the default color of normal text to green on a
black background, or black on a green background when reversed.
Note that white space cannot be used inside the attribute string
because of the current implementation of
.Xr config 8 .
.Pp
.Dl "options TERMINAL_NORM_ATTR=(FG_GREEN|BG_BLACK)"
.Pp
This line changes the default color of kernel messages to be bright red
on a black background, or black on a bright red background when reversed.
.Pp
.Dl "options TERMINAL_KERN_ATTR=(FG_LIGHTRED|BG_BLACK)"
.Sh SEE ALSO
.Xr kbdcontrol 1 ,
.Xr login 1 ,
.Xr vidcontrol 1 ,
.Xr atkbd 4 ,
.Xr atkbdc 4 ,
.Xr keyboard 4 ,
.Xr screen 4 ,
.Xr splash 4 ,
.Xr syscons 4 ,
.Xr ukbd 4 ,
.Xr vga 4 ,
.Xr kbdmap 5 ,
.Xr rc.conf 5 ,
.Xr ttys 5 ,
.Xr config 8 ,
.Xr getty 8 ,
.Xr kbdmux 8 ,
.Xr kldload 8 ,
.Xr moused 8
.Sh HISTORY
The
.Nm
driver first appeared in
.Fx 9.3 .
.Sh AUTHORS
.An -nosplit
The
.Nm
device driver was developed by
.An Ed Schouten Aq Mt ed@FreeBSD.org ,
.An Ed Maste Aq Mt emaste@FreeBSD.org ,
and
.An Aleksandr Rybalko Aq Mt ray@FreeBSD.org ,
with sponsorship provided by the
.Fx
Foundation.
This manual page was written by
.An Warren Block Aq Mt wblock@FreeBSD.org .
.Sh CAVEATS
Paste buffer size is limited by the system value
.Brq Dv MAX_INPUT ,
the number of bytes that can be stored in the terminal
input queue, usually 1024 bytes
(see
.Xr termios 4 ) .