DragonFly On-Line Manual Pages
SCREEN(4) DragonFly Kernel Interfaces Manual SCREEN(4)
NAME
screen -- pc display interface
DESCRIPTION
Access to the virtual consoles are obtained through the device files
/dev/ttyv0 - /dev/ttyvb. Each of these files correspond to a separate
virtual console. All virtual console devices can be open at once, but
only one is active at a time. The active virtual console "owns" the key-
board and display screen.
Output to a virtual console that not currently is on the display is saved
in a buffer that holds a "screenfull" (normally 25) lines. Any output
written to /dev/console (the original console device) is echoed to
/dev/ttyv0.
To switch between the virtual consoles one uses the sequence ALT+Fn,
which means hold down ALT and press one of the function keys. The vir-
tual console with the same number as the function key is then selected as
the current virtual console, and given exclusive use of the keyboard and
display. This switch sequence can be changed via the keyboard mapping
ioctl call (see keyboard(4)).
The console allows entering values that are not physically present on the
keyboard via a special keysequence. To use this facility press and hold
down ALT, then enter a decimal number from 0-255 via the numerical key-
pad, then release ALT. The entered value is then used as the ASCII value
for one character. This way it is possible to enter any ASCII value.
The console driver also includes a history function. It is activated by
pressing the scroll-lock key. This holds the display, and enables the
cursor arrows for scrolling up and down through the last scrolled out
lines.
The console understands a subset of the ANSI x3.64 character sequences.
For compatibility with the old pccons, the PC3 character sequences is
also supported.
ANSI Seq Function Termcap entry
======= ======= ===================================== ==============
-- E7 Save cursor position sc
-- E8 Restore saved cursor position rc
-- Ec Reset rs
-- EM move cursor up 1 line, --
scroll if at top
CUU E[nA move cursor up n lines up/UP (ku)
CUD E[nB move cursor down n lines do/DO (kd)
CUF E[nC move cursor right n characters nd/RI (kr)
CUB E[nD move cursor left n characters --/LE (kl)
HPA E[n` move cursor to character position n ch
HPR E[na move cursor right n characters --
VPA E[nd move cursor to line n cv
VPR E[ne move cursor down n lines --
CPL E[nF move cursor to start of line, -- (@7)
n lines up
CNL E[nE move cursor to start of line, nw
n lines down
CUP E[y;xH Move cursor to x, y cm
HVP E[y;xf Move cursor to x, y --
CBT E[nZ Move cursor back n tab stops bt (kB)
IL E[nL Insert n blank lines al/AL
ICH E[n@ Insert n blank characters ic/IC
DL E[nM Delete n lines dl/DL
DCH E[nP Delete n characters dc/DC
ED E[nJ Erase part or all of display: cd
n=0 from cursor to end of display,
n=1 from begin of display to cursor,
n=2 entire display.
EL E[nK Erase part or all of line: ce
n=0 from cursor to end of line,
n=1 from begin of line to cursor,
n=2 entire line.
ECH E[nX Erase n characters ec
SU E[nS Scroll display n lines up (forward) sf/SF
SD E[nT Scroll display n lines down (reverse) sr/SR
SGR E[nm Set character attributes: --
n= 0 normal attribute (all off)
n= 1 bold (highlight)
n= 4 underscore (if supported by HW)
n= 5 blink (if supported by HW)
n= 7 reverse
n= 22 remove bold
n= 24 remove underscore
n= 25 remove blink
n= 27 remove reverse
n= 3X set ANSI foreground color
(see table)
n= 4X set ANSI background color
(see table)
X=0 black X=1 red
X=2 green X=3 brown
X=4 blue X=5 magenta
X=6 cyan X=7 light grey
X=9 reset to the normal color
-- E[s Save cursor position sc
-- E[u Restore saved cursor position rc
-- E[x Reset normal colors and attributes --
to their default values
-- E[nz Switch to virtual console n --
-- E[1;nx Set normal ANSI background color --
to n (see table)
-- E[2;nx Set normal ANSI foreground color --
to n (see table)
-- E[3;nx Set normal video attribute directly --
to n (n from 0 to 255)
-- E[5;nx Set normal ANSI reverse background --
color to n (see table)
-- E[6;nx Set normal ANSI reverse foreground --
color to n (see table)
n= 0 black n= 8 dark grey
n= 1 red n= 9 light red
n= 2 green n=10 light green
n= 3 brown n=11 yellow
n= 4 blue n=12 light blue
n= 5 magenta n=13 light magenta
n= 6 cyan n=14 light cyan
n= 7 light grey n=15 white
-- E[7;nx Set normal reverse video attribute --
directly to n (n from 0 to 255)
-- E[=p;dB Set bell pitch (p) and duration (d), --
pitch is in units of 840 nS,
duration is units of 0,1 S.
-- E[=tC Set cursor type (see table) --
t=0 normal non-blinking
t=1 normal blinking
t=2 custom non-blinking
t=3 custom blinking
-- E[=s;eC Set custom cursor shape, where --
s is the starting and e is the ending
scanlines of the cursor.
-- E[=nA Set the border color to n --
(see table) (if supported by HW)
-- E[=nF Set normal foreground color to n --
(see table)
-- E[=nG Set normal background color to n --
(see table)
-- E[=nH Set normal reverse foreground color --
to n (see table)
-- E[=nI Set normal reverse background color --
to n (see table)
n= 0 black n= 8 dark grey
n= 1 blue n= 9 light blue
n= 2 green n=10 light green
n= 3 cyan n=11 light cyan
n= 4 red n=12 light red
n= 5 magenta n=13 light magenta
n= 6 brown n=14 yellow
n= 7 light grey n=15 white
note: the first E in the sequences stands for ESC (0x1b)
AUTHORS
Soren Schmidt <sos@FreeBSD.org>
DragonFly 3.5 October 6, 2000 DragonFly 3.5