Top ¶

4.1 The .screenrc file ¶

When screen is invoked, it executes initialization commands from the files .screenrc in the user’s home directory and /usr/local/etc/screenrc. These defaults can be overridden in the following ways: For the global screenrc file screen searches for the environment variable $SYSSCREENRC (this override feature may be disabled at compile-time). The user specific screenrc file is searched for in $SCREENRC, then $HOME/.screenrc. The command line option ‘-c’ specifies which file to use (see Invoking Screen). Commands in these files are used to set options, bind commands to keys, and to automatically establish one or more windows at the beginning of your screen session. Commands are listed one per line, with empty lines being ignored. A command’s arguments are separated by tabs or spaces, and may be surrounded by single or double quotes. A ‘#’ turns the rest of the line into a comment, except in quotes. Unintelligible lines are warned about and ignored. Commands may contain references to environment variables. The syntax is the shell-like $VAR or ${VAR}. Note that this causes incompatibility with previous screen versions, as now the ’$’-character has to be protected with ’\’ if no variable substitution is intended. A string in single-quotes is also protected from variable substitution.

Two configuration files are shipped as examples with your screen distribution: etc/screenrc and etc/etcscreenrc. They contain a number of useful examples for various commands.

4.2 Source ¶

Command: source file ¶

(none)
Read and execute commands from file file. Source commands may be nested to a maximum recursion level of ten. If file is not an absolute path and screen is already processing a source command, the parent directory of the running source command file is used to search for the new command file before screen’s current directory.

Note that termcap/terminfo/termcapinfo commands only work at startup and reattach time, so they must be reached via the default screenrc files to have an effect.

4.3 Colon ¶

Customization can also be done online, with this command:

Command: colon ¶

(C-a :)
Allows you to enter .screenrc command lines. Useful for on-the-fly modification of key bindings, specific window creation and changing settings. Note that the set keyword no longer exists, as of version 3.3. Change default settings with commands starting with ‘def’. You might think of this as the ex command mode of screen, with copy as its vi command mode (see Copy and Paste).

5.1 Default Key Bindings ¶

As mentioned previously, each keyboard command consists of a C-a followed by one other character. For your convenience, all commands that are bound to lower-case letters are also bound to their control character counterparts (with the exception of C-a a; see below). Thus, both C-a c and C-a C-c can be used to create a window.

The following table shows the default key bindings:

C-a '

(select)
Prompt for a window identifier and switch. See Selecting a Window.

C-a "

(windowlist -b)
Present a list of all windows for selection. See Selecting a Window.

C-a 0…9, -

(select 0…select 9, select -)
Switch to window number 0…9, or the blank window. See Selecting a Window.

C-a Tab

(focus)
Switch the input focus to the next region. See Regions.

C-a C-a

(other)
Toggle to the window displayed previously. If this window does no longer exist, other has the same effect as next. See Selecting a Window.

C-a a

(meta)
Send the command character (C-a) to window. See escape command. See Command Character.

C-a A

(title)
Allow the user to enter a title for the current window. See Naming Windows (Titles).

C-a b

C-a C-b

(break)
Send a break to the tty. See Break.

C-a B

(pow_break)
Close and reopen the tty-line. See Break.

C-a c

C-a C-c

(screen)
Create a new window with a shell and switch to that window. See Screen Command.

C-a C

(clear)
Clear the screen. See Clear.

C-a d

C-a C-d

(detach)
Detach screen from this terminal. See Detach.

C-a D D

(pow_detach)
Detach and logout. See Power Detach.

C-a f

C-a C-f

(flow)
Cycle flow among ‘on’, ‘off’ or ‘auto’. See Flow.

C-a F

(fit)
Resize the window to the current region size. See Fit.

C-a C-g

(vbell)
Toggle visual bell mode. See Bell.

C-a h

(hardcopy)
Write a hardcopy of the current window to the file “hardcopy.n”. See hardcopy.

C-a H

(log)
Toggle logging of the current window to the file “screenlog.n”. See log.

C-a i

C-a C-i

(info)
Show info about the current window. See Info.

C-a k

C-a C-k

(kill)
Destroy the current window. See Kill.

C-a l

C-a C-l

(redisplay)
Fully refresh the current window. See Redisplay.

C-a L

(login)
Toggle the current window’s login state. See Login.

C-a m

C-a C-m

(lastmsg)
Repeat the last message displayed in the message line. See Display Last Message.

C-a M

(monitor) Toggle monitoring of the current window. See Monitoring.

C-a SPC

C-a n

C-a C-n

(next)
Switch to the next window. See Selecting a Window.

C-a N

(number)
Show the number (and title) of the current window. See Number.

C-a p

C-a C-p

C-a C-h

C-a BackSpace

(prev)
Switch to the previous window (opposite of C-a n). See Selecting a Window.

C-a q

C-a C-q

(xon)
Send a ^Q (ASCII XON) to the current window. See XON and XOFF.

C-a Q

(only)
Delete all regions but the current one. See Regions.

C-a r

C-a C-r

(wrap)
Toggle the current window’s line-wrap setting (turn the current window’s automatic margins on or off). See Wrap.

C-a s

C-a C-s

(xoff)
Send a ^S (ASCII XOFF) to the current window. See XON and XOFF.

C-a S

(split)
Split the current region horizontally into two new ones. See Regions.

C-a t

C-a C-t

(time)
Show the load average and xref. See Time.

C-a v

(version)
Display the version and compilation date. See Version.

C-a C-v

(digraph)
Enter digraph. See Digraph.

C-a w

C-a C-w

(windows)
Show a list of active windows. See Windows.

C-a W

(width)
Toggle between 80 and 132 columns. See Window Size.

C-a x

C-a C-x

(lockscreen)
Lock your terminal. See Lock.

C-a X

(remove)
Kill the current region. See Regions.

C-a z

C-a C-z

(suspend)
Suspend screen. See Suspend.

C-a Z

(reset)
Reset the virtual terminal to its “power-on” values. See Reset.

C-a .

(dumptermcap)
Write out a .termcap file. See Write out the window’s termcap entry.

C-a ?

(help)
Show key bindings. See Help.

C-a \

(quit)
Kill all windows and terminate screen. See Quit.

C-a :

(colon)
Enter a command line. See Colon.

C-a [

C-a C-[

C-a ESC

(copy)
Enter copy/scrollback mode. See Copying.

C-a ]

C-a C-]

(paste .)
Write the contents of the paste buffer to the stdin queue of the current window. See Paste.

C-a {

C-a }

(history)
Copy and paste a previous (command) line. See History.

C-a >

(writebuf)
Write the paste buffer out to the screen-exchange file. See Screen Exchange.

C-a <

(readbuf)
Read the screen-exchange file into the paste buffer. See Screen Exchange.

C-a =

(removebuf)
Delete the screen-exchange file. See Screen Exchange.

C-a _

(silence)
Start/stop monitoring the current window for inactivity. See Monitoring.

C-a |

(split -v)
Split the current region vertically into two new ones. See Regions.

C-a ,

(license)
Show the copyright page. See License.

C-a *

(displays)
Show the listing of attached displays. See Displays.

5.2 Command Summary ¶

acladd usernames

Allow other users in this session. See Multiuser Session.

aclchg usernames permbits list

Change a user’s permissions. See Multiuser Session.

acldel username

Disallow other user in this session. See Multiuser Session.

aclgrp usrname [groupname]

Inherit permissions granted to a group leader. See Multiuser Session.

aclumask [users]+/-bits ...

Predefine access to new windows. See aclumask.

activity message

Set the activity notification message. See Monitoring.

addacl usernames

Synonym to acladd. See Multiuser Session.

allpartial state

Set all windows to partial refresh. See Redisplay.

altscreen state

Enables support for the "alternate screen" terminal capability. See Redisplay.

at [ident][#|*|%] command [args]

Execute a command at other displays or windows. See At.

attrcolor attrib [attribute/color-modifier]

Map attributes to colors. See Attrcolor.

autodetach state

Automatically detach the session on SIGHUP. See Detach.

autonuke state

Enable a clear screen to discard unwritten output. See Autonuke.

backtick id lifespan autorefresh command [args]

Define a command for the backtick string escape. See Backtick.

bce [state]

Change background color erase. See Character Processing.

bell_msg [message]

Set the bell notification message. See Bell.

bind [-c class] key [command [args]]

Bind a command to a key. See The bind command.

bindkey [opts] [string [cmd args]]

Bind a string to a series of keystrokes. See Bindkey.

blanker

Blank the screen. See Screen Saver.

blankerprg

Define a blanker program. See Screen Saver.

break [duration]

Send a break signal to the current window. See Break.

breaktype [tcsendbreak | TCSBRK | TIOCSBRK]

Specify how to generate breaks. See Break.

bufferfile [exchange-file]

Select a file for screen-exchange. See Screen Exchange.

bumpleft

Swaps window with previous one on window list. See Bumpleft.

bumpright

Swaps window with previous one on window list. See Bumpright.

c1 [state]

Change c1 code processing. See Character Processing.

caption mode [string]

Change caption mode and string. See Regions.

chacl usernames permbits list

Synonym to aclchg. See Multiuser Session.

charset set

Change character set slot designation. See Character Processing.

chdir [directory]

Change the current directory for future windows. See Chdir.

cjkwidth

Treat ambiguous width characters as full/half width. See Character Processing.

clear

Clear the window screen. See Clear.

colon

Enter a screen command. See Colon.

collapse

Reorders window on window list, removing number gaps between them. See Collapse.

command [-c class]

Simulate the screen escape key. See Command Character.

compacthist [state]

Selects compaction of trailing empty lines. See Scrollback.

console [state]

Grab or ungrab console output. See Console.

copy

Enter copy mode. See Copying.

copy_reg [key]

Removed. Use paste instead. See Registers.

crlf state

Select line break behavior for copying. See CR/LF.

debug state

Suppress/allow debugging output. See Debug.

defautonuke state

Select default autonuke behavior. See Autonuke.

defbce state

Select background color erase. See Character Processing.

defbreaktype [tcsendbreak | TCSBRK | TIOCSBRK]

Specify the default for generating breaks. See Break.

defc1 state

Select default c1 processing behavior. See Character Processing.

defcharset [set]

Change defaul character set slot designation. See Character Processing.

defencoding enc

Select default window encoding. See Character Processing.

defescape xy

Set the default command and meta characters. See Command Character.

defflow fstate

Select default flow control behavior. See Flow.

defgr state

Select default GR processing behavior. See Character Processing.

defhstatus [status]

Select default window hardstatus line. See Hardstatus.

deflog state

Select default window logging behavior. See log.

deflogin state

Select default utmp logging behavior. See Login.

defmode mode

Select default file mode for ptys. See Mode.

defmonitor state

Select default activity monitoring behavior. See Monitoring.

defmousetrack on|off

Select the default mouse tracking behavior. See Mousetrack.

defnonblock state|numsecs

Select default nonblock mode. See Nonblock.

defobuflimit limit

Select default output buffer limit. See Obuflimit.

defscrollback num

Set default lines of scrollback. See Scrollback.

defshell command

Set the default program for new windows. See Shell.

defsilence state

Select default idle monitoring behavior. See Monitoring.

defslowpaste msec

Select the default inter-character timeout when pasting. See Paste.

defutf8 state

Select default character encoding. See Character Processing.

defwrap state

Set default line-wrapping behavior. See Wrap.

defwritelock on|off|auto

Set default writelock behavior. See Multiuser Session.

zombie_timeout [seconds]

Try to reconnect dead windows after timeout. See Zombie.

detach [-h]

Disconnect screen from the terminal. See Detach.

digraph [preset [unicode-value]]

Enter a digraph sequence. See Digraph.

dinfo

Display terminal information. See Info.

displays

List currently active user interfaces. See Displays.

dumptermcap

Write the window’s termcap entry to a file. See Write out the window’s termcap entry.

echo [-n] message

Display a message on startup. See Startup.

encoding enc [denc]

Set the encoding of a window. See Character Processing.

escape xy

Set the command and meta characters. See Command Character.

eval command1 [command2 ...]

Parse and execute each argument. See Eval.

exec [[fdpat] command [args ...]]

Run a subprocess (filter). See Exec.

fit

Change window size to current display size. See Window Size.

flow [fstate]

Set flow control behavior. See Flow.

focus [next|prev|up|down|left|right|top|bottom]

Move focus to next region. See Regions.

focusminsize

Force the current region to a certain size. See Focusminsize.

gr [state]

Change GR charset processing. See Character Processing.

group [grouptitle]

Change or show the group the current window belongs to. See Window Groups.

hardcopy [-h] [file]

Write out the contents of the current window. See hardcopy.

hardcopy_append state

Append to hardcopy files. See hardcopy.

hardcopydir directory

Place, where to dump hardcopy files. See hardcopy.

hardstatus [state]

Use the hardware status line. See Hardware Status Line.

height [lines [cols]]

Set display height. See Window Size.

help [-c class]

Display current key bindings. See Help.

history

Find previous command beginning …. See History.

hstatus status

Change the window’s hardstatus line. See Hardstatus.

idle [timeout [cmd args]]

Define a screen saver command. See Screen Saver.

ignorecase [on|off]

Ignore character case in searches. See Searching.

info

Display window settings. See Info.

ins_reg [key]

Removed, use paste instead. See Registers.

kill

Destroy the current window. See Kill.

lastmsg

Redisplay the last message. See Display Last Message.

layout new [title]

Create a layout. See Layout.

layout remove [n|title]

Delete a layout. See Layout.

layout next

Select the next layout. See Layout.

layout prev

Select the previous layout. See Layout.

layout select [n|title]

Jump to a layout. See Layout.

layout show

List the available layouts. See Layout.

layout title [title]

Show or set the title of a layout. See Layout.

layout number [n]

Show or set the number of a layout. See Layout.

layout attach [title|:last]

Show or set which layout to reattach to. See Layout.

layout save [n|title]

Remember the organization of a layout. See Layout.

layout autosave [on|off]

Show or set the status of layout saving. See Layout.

layout dump [filename]

Save the layout arrangement to a file. See Layout.

license

Display licensing information. See Startup.

lockscreen

Lock the controlling terminal. See Lock.

log [state]

Log all output in the current window. See log.

logfile filename

Place where to collect logfiles. See log.

login [state]

Log the window in /etc/utmp. See Login.

logtstamp [state]

Configure logfile time-stamps. See log.

mapdefault

Use only the default mapping table for the next keystroke. See Bindkey Control.

mapnotnext

Don’t try to do keymapping on the next keystroke. See Bindkey Control.

maptimeout n

Set the inter-character timeout used for keymapping. See Bindkey Control.

markkeys string

Rebind keys in copy mode. See Markkeys.

maxwin n

Set the maximum window number. See Maxwin.

meta

Insert the command character. See Command Character.

monitor [state]

Monitor activity in window. See Monitoring.

mousetrack [on|off]

Enable selecting split regions with mouse clicks. See Mousetrack.

msgminwait sec

Set minimum message wait. See Message Wait.

msgwait sec

Set default message wait. See Message Wait.

multiuser state

Go into single or multi user mode. See Multiuser Session.

nethack state

Use nethack-like error messages. See Nethack.

next

Switch to the next window. See Selecting a Window.

nonblock [state|numsecs]

Disable flow control to the current display. See Nonblock.|numsecs]

number [n]

Change/display the current window’s number. See Number.

obuflimit [limit]

Select output buffer limit. See Obuflimit.

only

Kill all other regions. See Regions.

other

Switch to the window you were in last. See Selecting a Window.

partial state

Set window to partial refresh. See Redisplay.

password [crypted_pw]

Set reattach password. See Detach.

paste [src_regs [dest_reg]]

Paste contents of paste buffer or registers somewhere. See Paste.

pastefont [state]

Include font information in the paste buffer. See Paste.

pow_break

Close and Reopen the window’s terminal. See Break.

pow_detach

Detach and hang up. See Power Detach.

pow_detach_msg [message]

Set message displayed on pow_detach. See Power Detach.

prev

Switch to the previous window. See Selecting a Window.

printcmd [cmd]

Set a command for VT100 printer port emulation. See Printcmd.

process [key]

Treat a register as input to screen. See Registers.

quit

Kill all windows and exit. See Quit.

readbuf [-e encoding] [filename]

Read the paste buffer from the screen-exchange file. See Screen Exchange.

readreg [-e encoding] [reg [file]]

Load a register from paste buffer or file. See Registers.

redisplay

Redisplay the current window. See Redisplay.

register [-e encoding] key string

Store a string to a register. See Registers.

remove

Kill current region. See Regions.

removebuf

Delete the screen-exchange file. See Screen Exchange.

rendition bell | monitor | silence | so attr [color]

Change text attributes in caption for flagged windows. See Rendition.

reset

Reset the terminal settings for the window. See Reset.

resize [(+/-)lines]

Grow or shrink a region. See Resize.

screen [opts] [n] [cmd [args] | //group]

Create a new window. See Screen Command.

scrollback num

Set size of scrollback buffer. See Scrollback.

select [n|-|.]

Switch to a specified window. See Selecting a Window.

sessionname [name]

Name this session. See Session Name.

setenv [var [string]]

Set an environment variable for new windows. See Setenv.

setsid state

Control process group creation for windows. See Setsid.

shell command

Set the default program for new windows. See Shell.

shelltitle title

Set the default name for new windows. See Shell.

silence [state|seconds]

Monitor a window for inactivity. See Monitoring.

silencewait seconds

Default timeout to trigger an inactivity notify. See Monitoring.

sleep num

Pause during startup. See Startup.

slowpaste msec

Slow down pasting in windows. See Paste.

source file

Run commands from a file. See Source.

sorendition [attr [color]]

Deprecated. Use rendition so instead. See Rendition.

split

Split region into two parts. See Regions.

startup_message state

Display copyright notice on startup. See Startup.

stuff [string]

Stuff a string in the input buffer of a window. See Paste.

su [username [password [password2]]]

Identify a user. See Multiuser Session.

suspend

Put session in background. See Suspend.

term term

Set $TERM for new windows. See Term.

termcap term terminal-tweaks [window-tweaks]

Tweak termcap entries for best performance. See The termcap command.

terminfo term terminal-tweaks [window-tweaks]

Ditto, for terminfo systems. See The termcap command.

termcapinfo term terminal-tweaks [window-tweaks]

Ditto, for both systems. See The termcap command.

time [string]

Display time and load average. See Time.

title [windowtitle]

Set the name of the current window. See Title Command.

umask [users]+/-bits ...

Synonym to aclumask. See aclumask.

unbindall

Unset all keybindings. See The bind command.

unsetenv var

Unset environment variable for new windows. See Setenv.

utf8 [state [dstate]]

Select character encoding of the current window. See Character Processing.

vbell [state]

Use visual bell. See Bell.

vbell_msg [message]

Set vbell message. See Bell.

vbellwait sec

Set delay for vbell message. See Bell.

version

Display screen version. See Version.

wall message

Write a message to all displays. See Multiuser Session.

width [cols [lines]]

Set the width of the window. See Window Size.

windowlist [[-b] [-m] [-g]] | string [string] | title [title]

Present a list of all windows for selection. See Windowlist.

windows

List active windows. See Windows.

wrap [ on | off ]

Control line-wrap behavior. See Wrap.

writebuf [-e encoding] [filename]

Write paste buffer to screen-exchange file. See Screen Exchange.

writelock on|off|auto

Grant exclusive write permission. See Multiuser Session.

xoff

Send an XOFF character. See XON and XOFF.

xon

Send an XON character. See XON and XOFF.

zmodem [off|auto|catch|pass]

Define how screen treats zmodem requests. See Zmodem.

zombie [keys [onerror] ]

Keep dead windows. See Zombie.

6.1 Chdir ¶

Command: chdir [directory] ¶

(none)
Change the current directory of screen to the specified directory or, if called without an argument, to your home directory (the value of the environment variable $HOME). All windows that are created by means of the screen command from within .screenrc or by means of C-a : screen … or C-a c use this as their default directory. Without a chdir command, this would be the directory from which screen was invoked. Hardcopy and log files are always written to the window’s default directory, not the current directory of the process running in the window. You can use this command multiple times in your .screenrc to start various windows in different default directories, but the last chdir value will affect all the windows you create interactively.

6.2 Screen Command ¶

Command: screen [opts] [n] [cmd [args] | //group] ¶

(C-a c, C-a C-c)
Establish a new window. The flow-control options (‘-f’, ‘-fn’ and ‘-fa’), title option (‘-t’), login options (‘-l’ and ‘-ln’) , terminal type option (‘-T term’), the all-capability-flag (‘-a’) and scrollback option (‘-h num’) may be specified with each command. The option (‘-M’) turns monitoring on for this window. The option (‘-L’) turns output logging on for this window. If an optional number n in the range 0…MAXWIN-1 is given, the window number n is assigned to the newly created window (or, if this number is already in-use, the next available number). If a command is specified after screen, this command (with the given arguments) is started in the window; otherwise, a shell is created. If ‘//group’ is supplied, a container-type window is created in which other windows may be created inside it. See Window Groups.

Screen has built in some functionality of ‘cu’ and ‘telnet’. See Window Types.

Thus, if your .screenrc contains the lines

# example for .screenrc:
screen 1
screen -fn -t foobar 2 -L telnet foobar

screen creates a shell window (in window #1) and a window with a TELNET connection to the machine foobar (with no flow-control using the title ‘foobar’ in window #2) and will write a logfile ‘screenlog.2’ of the telnet session. If you do not include any screen commands in your .screenrc file, then screen defaults to creating a single shell window, number zero. When the initialization is completed, screen switches to the last window specified in your .screenrc file or, if none, it opens default window #0.

6.3 Setenv ¶

Command: setenv var string ¶

(none)
Set the environment variable var to value string. If only var is specified, the user will be prompted to enter a value. If no parameters are specified, the user will be prompted for both variable and value. The environment is inherited by all subsequently forked shells.

Command: unsetenv var ¶

(none)
Unset an environment variable.

6.4 Shell ¶

Command: shell command ¶

Command: defshell command ¶

(none)
Set the command to be used to create a new shell. This overrides the value of the environment variable $SHELL. This is useful if you’d like to run a tty-enhancer which is expecting to execute the program specified in $SHELL. If the command begins with a ‘-’ character, the shell will be started as a login-shell. Typical shells do only minimal initialization when not started as a login-shell. E.g. Bash will not read your ~/.bash_profile unless it is a login-shell.

defshell is currently a synonym to the shell .screenrc command.

Command: shelltitle title ¶

(none)
Set the title for all shells created during startup or by the C-a C-c command. See Naming Windows (Titles), for details about what titles are.

6.5 Term ¶

Command: term term ¶

(none)
In each window screen opens, it sets the $TERM variable to screen by default, unless no description for screen is installed in the local termcap or terminfo data base. In that case it pretends that the terminal emulator is ‘vt100’. This won’t do much harm, as screen is VT100/ANSI compatible. The use of the term command is discouraged for non-default purpose. That is, one may want to specify special $TERM settings (e.g. vt100) for the next screen rlogin othermachine command. Use the command screen -T vt100 rlogin othermachine rather than setting and resetting the default.

6.6 Window Types ¶

Screen provides three different window types. New windows are created with screen’s ‘screen’ command (see Screen Command). The first parameter to the ‘screen’ command defines which type of window is created. The different window types are all special cases of the normal type. They have been added in order to allow screen to be used efficiently as a console with 100 or more windows.

• The normal window contains a shell (default, if no parameter is given) or any other system command that could be executed from a shell. (e.g. ‘slogin’, etc...).
• If a tty (character special device) name (e.g. ‘/dev/ttya’) is specified as the first parameter, then the window is directly connected to this device. This window type is similar to ‘screen cu -l /dev/ttya’. Read and write access is required on the device node, an exclusive open is attempted on the node to mark the connection line as busy. An optional parameter is allowed consisting of a comma separated list of flags in the notation used by ‘stty(1)’:

  <baud_rate>

  Usually 300, 1200, 9600 or 19200. This affects transmission as well as receive speed.

  cs8 or cs7

  Specify the transmission of eight (or seven) bits per byte.

  cstopb or -cstopb

  Specify two (or one) stop bits per character

  parenb or -parenb

  Generate parity bit in output and expect parity bit in input

  parodd or -parodd

  Set odd (or even) parity

  ixon or -ixon

  Enables (or disables) software flow-control (CTRL-S/CTRL-Q) for sending data.

  ixoff or -ixoff

  Enables (or disables) software flow-control for receiving data.

  istrip or -istrip

  Clear (or keep) the eight bit in each received byte.

  You may want to specify as many of these options as applicable. Unspecified options cause the terminal driver to make up the parameter values of the connection. These values are system-dependent and may be in defaults or values saved from a previous connection.

  For tty windows, the info command shows some of the modem control lines in the status line. These may include ‘RTS’, ‘CTS’, ‘DTR’, ‘CD’ and more. This depends rather on on the available ioctl()’s and system header files than on the physical capabilities of the serial board. The name of a logical low (inactive) signal is preceded by an exclamation mark (‘!’), otherwise the signal is logical high (active). Unsupported but shown signals are usually shown low. When the CLOCAL status bit is true, the whole set of modem signals is placed inside curly braces (‘{’ and ‘}’). When the CRTSCTS or TIOCSOFTCAR bit is true, the signals ‘CTS’ or ‘CD’ are shown in parenthesis, respectively.

  For tty windows, the command break causes the Data transmission line (TxD) to go low for a specified period of time. This is expected to be interpreted as break signal on the other side. No data is sent and no modem control line is changed when a break is issued.

• If the first parameter is //telnet, the second parameter is expected to be a host name, and an optional third parameter may specify a TCP port number (default decimal 23). Screen will connect to a server listening on the remote host and use the telnet protocol to communicate with that server.

  For telnet windows, the command info shows details about the connection in square brackets (‘[’ and ‘]’) at the end of the status line.

  b

  BINARY. The connection is in binary mode.

  e

  ECHO. Local echo is disabled.

  c

  SGA. The connection is in ‘character mode’ (default: ‘line mode’).

  t

  TTYPE. The terminal type has been requested by the remote host. Screen sends the name screen unless instructed otherwise (see also the command ‘term’).

  w

  NAWS. The remote site is notified about window size changes.

  f

  LFLOW. The remote host will send flow control information. (Ignored at the moment.)

  Additional flags for debugging are ‘x’, ‘t’ and ‘n’ (XDISPLOC, TSPEED and NEWENV).

  For telnet windows, the command break sends the telnet code IAC BREAK (decimal 243) to the remote host.

6.7 Window Groups ¶

Screen provides a method for grouping windows together. Windows can be organized in a hierarchical fashion, resembling a tree structure. New screens are created using the screen command while new groups are created using screen //group. See Screen Command.

Once a new group is created, it will act as a container for windows and even other groups. When a group is selected, you will see the output of the windowlist command, allowing you to select a window inside. If there are no windows inside a group, use the screen command to create one. Once inside a group, using the commands next and prev will switch between windows only in that group. Using the windowlist command will give you the opportunity to leave the group you are in. See Windowlist.

Command: group [grouptitle] ¶

(none)
Change or show the group the current window belongs to. Windows can be moved around between different groups by specifying the name of the destination group. Without specifying a group, the title of the current group is displayed.

Using groups in combination with layouts will help create a multi-desktop experience. One group can be assigned for each layout made. Windows can be made, split, and organized within each group as desired. Afterwhich, switching between groups can be as easy as switching layouts.

7.1 Moving Back and Forth ¶

Command: next ¶

(C-a SPC, C-a n, C-a C-n)
Switch to the next window. This command can be used repeatedly to cycle through the list of windows. (On some terminals, C-SPC generates a NUL character, so you must release the control key before pressing space.)

Command: prev ¶

(C-a p, C-a C-p, C-a C-h, C-a Backspace)
Switch to the previous window (the opposite of C-a n).

7.2 Other Window ¶

Command: other ¶

(C-a C-a)
Switch to the last window displayed. Note that this command defaults to the command character typed twice, unless overridden. For instance, if you use the option ‘-e]x’, this command becomes ]] (see Command Character).

7.3 Select ¶

Command: select [n |-|.] ¶

(C-a n, C-a ')
Switch to the window with the number n. If no window number is specified, you get prompted for an identifier. This can be a window name (title) or a number. When a new window is established, the lowest available number is assigned to this window. Thus, the first window can be activated by select 0; there can be no more than 10 windows present simultaneously (unless screen is compiled with a higher MAXWIN setting). There are two special arguments, select - switches to the internal blank window and select . switches to the current window. The latter is useful if used with screen’s -X option.

7.4 Windowlist ¶

Command: windowlist [-b] [-m] [-g] ¶

Command: windowlist string [string] ¶

Command: windowlist title [title] ¶

(C-a ")
Display all windows in a table for visual window selection. If screen was in a window group, screen will back out of the group and then display the windows in that group. If the -b option is given, screen will switch to the blank window before presenting the list, so that the current window is also selectable. The -m option changes the order of the windows, instead of sorting by window numbers screen uses its internal most-recently-used list. The -g option will show the windows inside any groups in that level and downwards.

The following keys are used to navigate in windowlist:

k, C-p, or up Move up one line.

j, C-n, or down Move down one line.

C-g or escape Exit windowlist.

C-a or home Move to the first line.

C-e or end Move to the last line.

C-u or C-d Move one half page up or down.

C-b or C-f Move one full page up or down.

0..9 Using the number keys, move to the selected line.

mouseclick Move to the selected line. Available when mousetrack is set to on.

/ Search.

n Repeat search in the forward direction.

N Repeat search in the backward direction.

m Toggle MRU.

g Toggle group nesting.

a All window view.

C-h or backspace Back out the group.

, Switch numbers with the previous window.

. Switch numbers with the next window.

K Kill that window.

space or enter Select that window.

The table format can be changed with the string and title option, the title is displayed as table heading, while the lines are made by using the string setting. The default setting is ‘Num Name%=Flags’ for the title and ‘%3n %t%=%f’ for the lines. See the string escapes chapter (see String Escapes) for more codes (e.g. color settings).

Windowlist needs a region size of at least 10 characters wide and 6 characters high in order to display.

8.1 Detach ¶

Command: autodetach state ¶

(none)
Sets whether screen will automatically detach upon hangup, which saves all your running programs until they are resumed with a screen -r command. When turned off, a hangup signal will terminate screen and all the processes it contains. Autodetach is on by default.

Command: detach ¶

(C-a d, C-a C-d)
Detach the screen session (disconnect it from the terminal and put it into the background). A detached screen can be resumed by invoking screen with the -r option (see Invoking Screen). The -h option tells screen to immediately close the connection to the terminal (‘hangup’).

Command: password [crypted_pw] ¶

(none)
Present a crypted password in your .screenrc file and screen will ask for it, whenever someone attempts to resume a detached session. This is useful, if you have privileged programs running under screen and you want to protect your session from reattach attempts by users that managed to assume your uid. (I.e. any superuser.) If no crypted password is specified, screen prompts twice a password and places its encryption in the paste buffer. Default is ‘none’, which disables password checking.

8.2 Power Detach ¶

Command: pow_detach ¶

(C-a D D)
Mainly the same as detach, but also sends a HANGUP signal to the parent process of screen.
Caution: This will result in a logout if screen was started from your login-shell.

Command: pow_detach_msg [message] ¶

(none)
The message specified here is output whenever a power detach is performed. It may be used as a replacement for a logout message or to reset baud rate, etc. Without a parameter, the current message is shown.

8.3 Lock ¶

Command: lockscreen ¶

(C-a x, C-a C-x)
Call a screenlock program. Screen does not accept any command keys until this program terminates. Meanwhile processes in the windows may continue, as the windows are in the detached state. The screenlock program may be changed through the environment variable $LOCKPRG (which must be set in the shell from which screen is started) and is executed with the user’s uid and gid.

Warning: When you leave other shells unlocked and have no password set on screen, the lock is void: One could easily re-attach from an unlocked shell. This feature should rather be called lockterminal.

8.4 Multiuser Session ¶

These commands allow other users to gain access to one single screen session. When attaching to a multiuser screen the sessionname is specified as username/sessionname to the -S command line option. Screen must be compiled with multiuser support to enable features described here.

• Multiuser
• Acladd
• Aclchg
• Acldel
• Aclgrp
• Displays
• aclumask
• Wall
• Writelock
• Su

8.5 Session Name ¶

Command: sessionname [name] ¶

(none)
Rename the current session. Note that for screen -list the name shows up with the process-id prepended. If the argument name is omitted, the name of this session is displayed.
Caution: The $STY environment variable will still reflect the old name in pre-existing shells. This may result in confusion. Use of this command is generally discouraged. Use the -S command-line option if you want to name a new session.The default is constructed from the tty and host names.

8.6 Suspend ¶

Command: suspend ¶

(C-a z, C-a C-z)
Suspend screen. The windows are in the detached state while screen is suspended. This feature relies on the parent shell being able to do job control.

8.7 Quit ¶

Command: quit ¶

(C-a \)
Kill all windows and terminate screen. (see Key Binding).

9.1 Split ¶

Command: split [-v] ¶

(C-a S, C-a |)
Split the current region into two new ones. All regions on the display are resized to make room for the new region. The blank window is displayed in the new region. The default is to create a horizontal split, putting the new regions on the top and bottom of each other. Using ‘-v’ will create a vertical split, causing the new regions to appear side by side of each other. Use the remove or the only command to delete regions. Use focus to toggle between regions.

When a region is split opposite of how it was previously split (that is, vertical then horizontal or horizontal then vertical), a new layer is created. The layer is used to group together the regions that are split the same. Normally, as a user, you should not see nor have to worry about layers, but they will affect how some commands (focus and resize) behave.

With this current implementation of screen, scrolling data will appear much slower in a vertically split region than one that is not. This should be taken into consideration if you need to use system commands such as cat or tail -f.

9.2 Focus ¶

Command: focus [ next|prev|up|down|left|right|top|bottom ] ¶

(C-a Tab)
Move the input focus to the next region. This is done in a cyclic way so that the top left region is selected after the bottom right one. If no option is given it defaults to next. The next region to be selected is determined by how the regions are layered. Normally, the next region in the same layer would be selected. However, if that next region contains one or more layers, the first region in the highest layer is selected first. If you are at the last region of the current layer, next will move the focus to the next region in the lower layer (if there is a lower layer). Prev cycles in the opposite order. See Split for more information about layers.

The rest of the options (up, down, left, right, top, and bottom) are more indifferent to layers. The option up will move the focus upward to the region that is touching the upper left corner of the current region. Down will move downward to the region that is touching the lower left corner of the current region. The option left will move the focus leftward to the region that is touching the upper left corner of the current region, while right will move rightward to the region that is touching the upper right corner of the current region. Moving left from a left most region or moving right from a right most region will result in no action.

The option top will move the focus to the very first region in the upper list corner of the screen, and bottom will move to the region in the bottom right corner of the screen. Moving up from a top most region or moving down from a bottom most region will result in no action.

Useful bindings are (h, j, k, and l as in vi):

bind h focus left
bind j focus down
bind k focus up
bind l focus right
bind t focus top
bind b focus bottom

Note that ‘k’ is traditionally bound to the kill command.

9.3 Only ¶

Command: only ¶

(C-a Q)
Kill all regions but the current one.

9.4 Remove ¶

Command: remove ¶

(C-a X)
Kill the current region. This is a no-op if there is only one region.

9.5 Resize ¶

Command: resize [-h|-v|-b|-l|-p] [ [+|-]n[%] | = | max | min | _ | 0 ] ¶

(none)
Resize the current region. The space will be removed from or added to the surrounding regions depending on the order of the splits. The available options for resizing are ‘-h’(horizontal), ‘-v’(vertical), ‘-b’(both), ‘-l’(local to layer), and ‘-p’(perpendicular). Horizontal resizes will add or remove width to a region, vertical will add or remove height, and both will add or remove size from both dimensions. Local and perpendicular are similar to horizontal and vertical, but they take in account of how a region was split. If a region’s last split was horizontal, a local resize will work like a vertical resize. If a region’s last split was vertical, a local resize will work like a horizontal resize. Perpendicular resizes work in opposite of local resizes. If no option is specified, local is the default.

The amount of lines to add or remove can be expressed a couple of different ways. By specifying a number n by itself will resize the region by that absolute amount. You can specify a relative amount by prefixing a plus ‘+’ or minus ‘-’ to the amount, such as adding +n lines or removing -n lines. Resizing can also be expressed as an absolute or relative percentage by postfixing a percent sign ‘%’. Using zero ‘0’ is a synonym for min and using an underscore ‘_’ is a synonym for max.

Some examples are:

resize +N       increase current region by N
resize -N       decrease current region by N
resize N        set current region to N
resize 20%      set current region to 20% of original size
resize +20%     increase current region by 20%
resize -b =     make all windows equally
resize max      maximize current region
resize min      minimize current region

Without any arguments, screen will prompt for how you would like to resize the current region.

See focusminsize if you want to restrict the minimum size a region can have.

9.6 Caption ¶

Command: caption always|splitonly [string] ¶

Command: caption string [string] ¶

(none)
This command controls the display of the window captions. Normally a caption is only used if more than one window is shown on the display (split screen mode). But if the type is set to always, screen shows a caption even if only one window is displayed. The default is ‘splitonly’.

The second form changes the text used for the caption. You can use all string escapes (see String Escapes). Screen uses a default of ‘%3n %t’.

You can mix both forms by providing the string as an additional argument.

9.7 Fit ¶

Command: fit ¶

(C-a F)
Change the window size to the size of the current region. This command is needed because screen doesn’t adapt the window size automatically if the window is displayed more than once.

9.8 Focusminsize ¶

Command: focusminsize [ (width|max|_) (height|max|_) ] ¶

(none)
This forces any currently selected region to be automatically resized at least a certain width and height. All other surrounding regions will be resized in order to accommodate. This constraint follows every time the focus command is used. The resize command can be used to increase either dimension of a region, but never below what is set with focusminsize. The underscore ‘_’ is a synonym for max. Setting a width and height of 0 0 (zero zero) will undo any constraints and allow for manual resizing. Without any parameters, the minimum width and height is shown.

9.9 Layout ¶

Using regions, and perhaps a large enough terminal, you can give screen more of a desktop feel. By being able to split regions horizontally or vertically, you can take advantage of the lesser used spaces of your terminal. The catch to these splits has been that they’re not kept between screen detachments and reattachments.

Layouts will help organize your regions. You can create one layout of four horizontal regions and then create a separate layout of regions in a two by two array. The regions could contain the same windows, but they don’t have to. You can easily switch between layouts and keep them between detachments and reattachments.

Note that there are several subcommands to layout.

Command: layout new [title] ¶

(none)
Create a new layout. The screen will change to one whole region and be switched to the blank window. From here, you build the regions and the windows they show as you desire. The new layout will be numbered with the smallest available integer, starting with zero. You can optionally give a title to your new layout. Otherwise, it will have a default title of layout. You can always change the title later by using the command layout title.

Command: layout remove [n|title] ¶

(none)
Remove, or in other words, delete the specified layout. Either the number or the title can be specified. Without either specification, screen will remove the current layout.

Removing a layout does not affect your set windows or regions.

Command: layout next ¶

(none)
Switch to the next layout available

Command: layout prev ¶

(none)
Switch to the previous layout available

Command: layout select [n|title] ¶

(none)
Select the desired layout. Either the number or the title can be specified. Without either specification, screen will prompt and ask which screen is desired. To see which layouts are available, use the layout show command.

Command: layout show ¶

(none)
List on the message line the number(s) and title(s) of the available layout(s). The current layout is flagged.

Command: layout title [title] ¶

(none)
Change or display the title of the current layout. A string given will be used to name the layout. Without any options, the current title and number is displayed on the message line.

Command: layout number [n] ¶

(none)
Change or display the number of the current layout. An integer given will be used to number the layout. Without any options, the current number and title is displayed on the message line.

Command: layout attach [title|:last] ¶

(none)
Change or display which layout to reattach back to. The default is :last, which tells screen to reattach back to the last used layout just before detachment. By supplying a title, You can instruct screen to reattach to a particular layout regardless which one was used at the time of detachment. Without any options, the layout to reattach to will be shown in the message line.

Command: layout save [n|title] ¶

(none)
Remember the current arrangement of regions. When used, screen will remember the arrangement of vertically and horizontally split regions. This arrangement is restored when a screen session is reattached or switched back from a different layout. If the session ends or the screen process dies, the layout arrangements are lost. The layout dump command should help in this siutation. If a number or title is supplied, screen will remember the arrangement of that particular layout. Without any options, screen will remember the current layout.

Saving your regions can be done automatically by using the layout autosave command.

Command: layout autosave [on|off] ¶

(none)
Change or display the status of automatically saving layouts. The default is on, meaning when screen is detached or changed to a different layout, the arrangement of regions and windows will be remembered at the time of change and restored upon return. If autosave is set to off, that arrangement will only be restored to either to the last manual save, using layout save, or to when the layout was first created, to a single region with a single window. Without either an on or an off, the current status is displayed on the message line.

Command: layout dump [filename] ¶

(none)
Write to a file the order of splits made in the current layout. This is useful to recreate the order of your regions used in your current layout. Only the current layout is recorded. While the order of the regions are recorded, the sizes of those regions and which windows correspond to which regions are not. If no filename is specified, the default is layout-dump, saved in the directory that the screen process was started in. If the file already exists, layout dump will append to that file. As an example:

layout dump /home/user/.screenrc

will save or append the layout to the user’s .screenrc file.

10.1 Naming Windows (Titles) ¶

You can customize each window’s name in the window display (viewed with the windows command (see Windows) by setting it with one of the title commands. Normally the name displayed is the actual command name of the program created in the window. However, it is sometimes useful to distinguish various programs of the same name or to change the name on-the-fly to reflect the current state of the window.

The default name for all shell windows can be set with the shelltitle command (see Shell). You can specify the name you want for a window with the ‘-t’ option to the screen command when the window is created (see Screen Command). To change the name after the window has been created you can use the title-string escape-sequence (ESC k name ESC \) and the title command (C-a A). The former can be output from an application to control the window’s name under software control, and the latter will prompt for a name when typed. You can also bind predefined names to keys with the title command to set things quickly without prompting.

• Title Command
• Dynamic Titles
• Setting up your prompt for shell titles
• Setting up shell titles in your .screenrc

set prompt='{No value for `esc'}[0000m{No value for `esc'}k{No value for `esc'}\% '

set prompt="%{\ek\e\\%}\% "

PROMPT_COMMAND='printf "\033k\033\134"'

screen -t top 2 nice top

shelltitle '> |csh'
screen 1

/usr/joe/src/dir> trn

bind R screen -t '% |root:' su

% !em
emacs file.c

bind o title
bind E title ""
bind u title (unknown)

10.2 Console ¶

Command: console [state] ¶

(none)
Grabs or un-grabs the machines console output to a window. When the argument is omitted the current state is displayed. Note: Only the owner of /dev/console can grab the console output. This command is only available if the host supports the ioctl TIOCCONS.

10.3 Kill ¶

Command: kill ¶

(C-a k, C-a C-k)
Kill the current window.
If there is an exec command running (see Exec) then it is killed. Otherwise the process (e.g. shell) running in the window receives a HANGUP condition, the window structure is removed and screen (your display) switches to another window. When the last window is destroyed, screen exits. After a kill screen switches to the previously displayed window.
Caution: emacs users may find themselves killing their emacs session when trying to delete the current line. For this reason, it is probably wise to use a different command character (see Command Character) or rebind kill to another key sequence, such as C-a K (see Key Binding).

10.4 Login ¶

Command: deflogin state ¶

(none)
Same as the login command except that the default setting for new windows is changed. This defaults to ‘on’ unless otherwise specified at compile time (see Installation). Both commands are only present when screen has been compiled with utmp support.

Command: login [state] ¶

(C-a L)
Adds or removes the entry in /etc/utmp for the current window. This controls whether or not the window is logged in. In addition to this toggle, it is convenient to have “log in” and “log out” keys. For instance, bind I login on and bind O login off will map these keys to be C-a I and C-a O (see Key Binding).

10.5 Mode ¶

Command: defmode mode ¶

(none)
The mode of each newly allocated pseudo-tty is set to mode. mode is an octal number as used by chmod(1). Defaults to 0622 for windows which are logged in, 0600 for others (e.g. when -ln was specified for creation, see Screen Command).

10.6 Monitoring ¶

Command: activity message ¶

(none)
When any activity occurs in a background window that is being monitored, screen displays a notification in the message line. The notification message can be redefined by means of the activity command. Each occurrence of ‘%’ in message is replaced by the number of the window in which activity has occurred, and each occurrence of ‘^G’ is replaced by the definition for bell in your termcap (usually an audible bell). The default message is

'Activity in window %n'

Note that monitoring is off for all windows by default, but can be altered by use of the monitor command (C-a M).

Command: defmonitor state ¶

(none)
Same as the monitor command except that the default setting for new windows is changed. Initial setting is ‘off’.

Command: monitor [state] ¶

(C-a M)
Toggles monitoring of the current window. When monitoring is turned on and the affected window is switched into the background, the activity notification message will be displayed in the status line at the first sign of output, and the window will also be marked with an ‘@’ in the window-status display (see Windows). Monitoring defaults to ‘off’ for all windows.

Command: silence [state|sec] ¶

(C-a _)
Toggles silence monitoring of windows. When silence is turned on and an affected window is switched into the background, you will receive the silence notification message in the status line after a specified period of inactivity (silence). The default timeout can be changed with the silencewait command or by specifying a number of seconds instead of on or off. Silence is initially off for all windows.

Command: defsilence state ¶

(none)
Same as the silence command except that the default setting for new windows is changed. Initial setting is ‘off’.

Command: silencewait seconds ¶

(none)
Define the time that all windows monitored for silence should wait before displaying a message. Default is 30 seconds.

10.7 Windows ¶

Command: windows [ string ] ¶

(C-a w, C-a C-w)
Uses the message line to display a list of all the windows. Each window is listed by number with the name of the program running in the window (or its title).

The current window is marked with a ‘*’; the previous window is marked with a ‘-’; all the windows that are logged in are marked with a ‘$’ (see Login); a background window that has received a bell is marked with a ‘!’; a background window that is being monitored and has had activity occur is marked with an ‘@’ (see Monitoring); a window which has output logging turned on is marked with ‘(L)’; windows occupied by other users are marked with ‘&’ or ‘&&’ if the window is shared by other users; windows in the zombie state are marked with ‘Z’.

If this list is too long to fit on the terminal’s status line only the portion around the current window is displayed.

You can customize the output format to any string you like including string escapes (see String Escapes). In this case, if the string parameter is passed, the maximum output size is unlimited (instead of 1024 bytes if no parameter is passed).

10.8 Hardstatus ¶

Screen maintains a hardstatus line for every window. If a window gets selected, the display’s hardstatus will be updated to match the window’s hardstatus line. The hardstatus line can be changed with the ANSI Application Program Command (APC): ‘ESC_<string>ESC\’. As a convenience for xterm users the sequence ‘ESC]0..2;<string>^G’ is also accepted.

Command: defhstatus [status] ¶

(none)
The hardstatus line that all new windows will get is set to status. This command is useful to make the hardstatus of every window display the window number or title or the like. status may contain the same directives as in the window messages, but the directive escape character is ‘^E’ (octal 005) instead of ‘%’. This was done to make a misinterpretation of program generated hardstatus lines impossible. If the parameter status is omitted, the current default string is displayed. Per default the hardstatus line of new windows is empty.

Command: hstatus status ¶

(none)
Changes the current window’s hardstatus line to status.

10.9 Mousetrack ¶

Command: mousetrack [ on|off ] ¶

(none)
This command determines whether screen will watch for mouse clicks. When this command is enabled, regions that have been split in various ways can be selected by pointing to them with a mouse and left-clicking them. Without specifying on or off, the current state is displayed. The default state is determined by the defmousetrack command.

Command: defmousetrack on|off ¶

(none)
This command determines the default state of the mousetrack command, currently defaulting of off.

11.1 Control Sequences ¶

The following is a list of control sequences recognized by screen. ‘(V)’ and ‘(A)’ indicate VT100-specific and ANSI- or ISO-specific functions, respectively.

ESC E                           Next Line
ESC D                           Index
ESC M                           Reverse Index
ESC H                           Horizontal Tab Set
ESC Z                           Send VT100 Identification String
ESC 7                   (V)     Save Cursor and Attributes
ESC 8                   (V)     Restore Cursor and Attributes
ESC [s                  (A)     Save Cursor and Attributes
ESC [u                  (A)     Restore Cursor and Attributes
ESC c                           Reset to Initial State
ESC g                           Visual Bell
ESC Pn p                        Cursor Visibility (97801)
    Pn = 6                      Invisible
         7                      Visible
ESC =                   (V)     Application Keypad Mode
ESC >                   (V)     Numeric Keypad Mode
ESC # 8                 (V)     Fill Screen with E's
ESC \                   (A)     String Terminator
ESC ^                   (A)     Privacy Message String (Message Line)
ESC !                           Global Message String (Message Line)
ESC k                           Title Definition String
ESC P                   (A)     Device Control String
                                Outputs a string directly to the host
                                terminal without interpretation.
ESC _                   (A)     Application Program Command (Hardstatus)
ESC ] 0 ; string ^G     (A)     Operating System Command (Hardstatus, xterm
                                title hack)
ESC ] 83 ; cmd ^G       (A)     Execute screen command. This only works if
                                multi-user support is compiled into screen.
                                The pseudo-user ":window:" is used to check
                                the access control list. Use "addacl :window:
                                -rwx #?" to create a user with no rights and
                                allow only the needed commands.
Control-N               (A)     Lock Shift G1 (SO)
Control-O               (A)     Lock Shift G0 (SI)
ESC n                   (A)     Lock Shift G2
ESC o                   (A)     Lock Shift G3
ESC N                   (A)     Single Shift G2
ESC O                   (A)     Single Shift G3
ESC ( Pcs               (A)     Designate character set as G0
ESC ) Pcs               (A)     Designate character set as G1
ESC * Pcs               (A)     Designate character set as G2
ESC + Pcs               (A)     Designate character set as G3
ESC [ Pn ; Pn H                 Direct Cursor Addressing
ESC [ Pn ; Pn f                 same as above
ESC [ Pn J                      Erase in Display
      Pn = None or 0            From Cursor to End of Screen
           1                    From Beginning of Screen to Cursor
           2                    Entire Screen
ESC [ Pn K                      Erase in Line
      Pn = None or 0            From Cursor to End of Line
           1                    From Beginning of Line to Cursor
           2                    Entire Line
ESC [ Pn X                      Erase character
ESC [ Pn A                      Cursor Up
ESC [ Pn B                      Cursor Down
ESC [ Pn C                      Cursor Right
ESC [ Pn D                      Cursor Left
ESC [ Pn E                      Cursor next line
ESC [ Pn F                      Cursor previous line
ESC [ Pn G                      Cursor horizontal position
ESC [ Pn `                      same as above
ESC [ Pn d                      Cursor vertical position
ESC [ Ps ;...; Ps m             Select Graphic Rendition
      Ps = None or 0            Default Rendition
           1                    Bold
           2            (A)     Faint
           3            (A)     Standout Mode (ANSI: Italicized)
           4                    Underlined
           5                    Blinking
           7                    Negative Image
           22           (A)     Normal Intensity
           23           (A)     Standout Mode off (ANSI: Italicized off)
           24           (A)     Not Underlined
           25           (A)     Not Blinking
           27           (A)     Positive Image
           30           (A)     Foreground Black
           31           (A)     Foreground Red
           32           (A)     Foreground Green
           33           (A)     Foreground Yellow
           34           (A)     Foreground Blue
           35           (A)     Foreground Magenta
           36           (A)     Foreground Cyan
           37           (A)     Foreground White
           39           (A)     Foreground Default
           40           (A)     Background Black
           ...                  ...
           49           (A)     Background Default
ESC [ Pn g                      Tab Clear
      Pn = None or 0            Clear Tab at Current Position
           3                    Clear All Tabs
ESC [ Pn ; Pn r         (V)     Set Scrolling Region
ESC [ Pn I              (A)     Horizontal Tab
ESC [ Pn Z              (A)     Backward Tab
ESC [ Pn L              (A)     Insert Line
ESC [ Pn M              (A)     Delete Line
ESC [ Pn @              (A)     Insert Character
ESC [ Pn P              (A)     Delete Character
ESC [ Pn S                      Scroll Scrolling Region Up
ESC [ Pn T                      Scroll Scrolling Region Down
ESC [ Pn ^                      same as above
ESC [ Ps ;...; Ps h             Set Mode
ESC [ Ps ;...; Ps l             Reset Mode
      Ps = 4            (A)     Insert Mode
           20           (A)     ‘Automatic Linefeed’ Mode.
           34                   Normal Cursor Visibility
           ?1           (V)     Application Cursor Keys
           ?3           (V)     Change Terminal Width to 132 columns
           ?5           (V)     Reverse Video
           ?6           (V)     ‘Origin’ Mode
           ?7           (V)     ‘Wrap’ Mode
           ?9                   X10 mouse tracking
           ?25          (V)     Visible Cursor
           ?47                  Alternate Screen (old xterm code)
           ?1000        (V)     VT200 mouse tracking
           ?1047                Alternate Screen (new xterm code)
           ?1049                Alternate Screen (new xterm code)
ESC [ 5 i               (A)     Start relay to printer (ANSI Media Copy)
ESC [ 4 i               (A)     Stop relay to printer (ANSI Media Copy)
ESC [ 8 ; Ph ; Pw t             Resize the window to ‘Ph’ lines and
                                ‘Pw’ columns (SunView special)
ESC [ c                         Send VT100 Identification String
ESC [ x                 (V)     Send Terminal Parameter Report
ESC [ > c                       Send Secondary Device Attributes String
ESC [ 6 n                       Send Cursor Position Report

11.2 Input Translation ¶

In order to do a full VT100 emulation screen has to detect that a sequence of characters in the input stream was generated by a keypress on the user’s keyboard and insert the VT100 style escape sequence. Screen has a very flexible way of doing this by making it possible to map arbitrary commands on arbitrary sequences of characters. For standard VT100 emulation the command will always insert a string in the input buffer of the window (see also command stuff, see Paste). Because the sequences generated by a keypress can change after a reattach from a different terminal type, it is possible to bind commands to the termcap name of the keys. Screen will insert the correct binding after each reattach. See Bindkey for further details on the syntax and examples.

Here is the table of the default key bindings. (A) means that the command is executed if the keyboard is switched into application mode.

Key name        Termcap name    Command
-----------------------------------------------------
Cursor up            ku         stuff \033[A
                                stuff \033OA      (A)
Cursor down          kd         stuff \033[B
                                stuff \033OB      (A)
Cursor right         kr         stuff \033[C
                                stuff \033OC      (A)
Cursor left          kl         stuff \033[D
                                stuff \033OD      (A)
Function key 0       k0         stuff \033[10~
Function key 1       k1         stuff \033OP
Function key 2       k2         stuff \033OQ
Function key 3       k3         stuff \033OR
Function key 4       k4         stuff \033OS
Function key 5       k5         stuff \033[15~
Function key 6       k6         stuff \033[17~
Function key 7       k7         stuff \033[18~
Function key 8       k8         stuff \033[19~
Function key 9       k9         stuff \033[20~
Function key 10      k;         stuff \033[21~
Function key 11      F1         stuff \033[23~
Function key 12      F2         stuff \033[24~
Home                 kh         stuff \033[1~
End                  kH         stuff \033[4~
Insert               kI         stuff \033[2~
Delete               kD         stuff \033[3~
Page up              kP         stuff \033[5~
Page down            kN         stuff \033[6~
Keypad 0             f0         stuff 0
                                stuff \033Op      (A)
Keypad 1             f1         stuff 1
                                stuff \033Oq      (A)
Keypad 2             f2         stuff 2
                                stuff \033Or      (A)
Keypad 3             f3         stuff 3
                                stuff \033Os      (A)
Keypad 4             f4         stuff 4
                                stuff \033Ot      (A)
Keypad 5             f5         stuff 5
                                stuff \033Ou      (A)
Keypad 6             f6         stuff 6
                                stuff \033Ov      (A)
Keypad 7             f7         stuff 7
                                stuff \033Ow      (A)
Keypad 8             f8         stuff 8
                                stuff \033Ox      (A)
Keypad 9             f9         stuff 9
                                stuff \033Oy      (A)
Keypad +             f+         stuff +
                                stuff \033Ok      (A)
Keypad -             f-         stuff -
                                stuff \033Om      (A)
Keypad *             f*         stuff *
                                stuff \033Oj      (A)
Keypad /             f/         stuff /
                                stuff \033Oo      (A)
Keypad =             fq         stuff =
                                stuff \033OX      (A)
Keypad .             f.         stuff .
                                stuff \033On      (A)
Keypad ,             f,         stuff ,
                                stuff \033Ol      (A)
Keypad enter         fe         stuff \015
                                stuff \033OM      (A)

11.3 Digraph ¶

Command: digraph [preset [unicode-value]] ¶

(C-a C-v)
This command prompts the user for a digraph sequence. The next two characters typed are looked up in a builtin table and the resulting character is inserted in the input stream. For example, if the user enters ‘a"’, an a-umlaut will be inserted. If the first character entered is a 0 (zero), screen will treat the following characters (up to three) as an octal number instead. The optional argument preset is treated as user input, thus one can create an "umlaut" key. For example the command ‘bindkey ^K digraph '"'’ enables the user to generate an a-umlaut by typing ‘CTRL-K a’. When a non-zero unicode-value is specified, a new digraph is created with the specified preset. The digraph is unset if a zero value is provided for the unicode-value.

The following table is the builtin sequences.

     Sequence   Octal   Digraph   Unicode Equivalent
     -----------------------------------------------
     ' ', ' '    160    (space)         U+00A0
     'N', 'S'    160    (space)         U+00A0
     '~', '!'    161       ¡            U+00A1
     '!', '!'    161       ¡            U+00A1
     '!', 'I'    161       ¡            U+00A1
     'c', '|'    162       ¢            U+00A2
     'c', 't'    162       ¢            U+00A2
     '$', '$'    163       £            U+00A3
     'P', 'd'    163       £            U+00A3
     'o', 'x'    164       ¤            U+00A4
     'C', 'u'    164       ¤            U+00A4
     'C', 'u'    164       ¤            U+00A4
     'E', 'u'    164       ¤            U+00A4
     'Y', '-'    165       ¥            U+00A5
     'Y', 'e'    165       ¥            U+00A5
     '|', '|'    166       ¦            U+00A6
     'B', 'B'    166       ¦            U+00A6
     'p', 'a'    167       §            U+00A7
     'S', 'E'    167       §            U+00A7
     '"', '"'    168       ¨            U+00A8
     ''', ':'    168       ¨            U+00A8
     'c', 'O'    169       ©            U+00A9
     'C', 'o'    169       ©            U+00A9
     'a', '-'    170       ª            U+00AA
     '<', '<'    171       «            U+00AB
     '-', ','    172       ¬            U+00AC
     'N', 'O'    172       ¬            U+00AC
     '-', '-'    173       ­            U+00AD
     'r', 'O'    174       ®            U+00AE
     'R', 'g'    174       ®            U+00AE
     '-', '='    175       ¯            U+00AF
     ''', 'm'    175       ¯            U+00AF
     '~', 'o'    176       °            U+00B0
     'D', 'G'    176       °            U+00B0
     '+', '-'    177       ±            U+00B1
     '2', '2'    178       ²            U+00B2
     '2', 'S'    178       ²            U+00B2
     '3', '3'    179       ³            U+00B3
     '3', 'S'    179       ³            U+00B3
     ''', '''    180       ´            U+00B4
     'j', 'u'    181       µ            U+00B5
     'M', 'y'    181       µ            U+00B5
     'p', 'p'    182       ¶            U+00B6
     'P', 'I'    182       ¶            U+00B6
     '~', '.'    183       ·            U+00B7
     '.', 'M'    183       ·            U+00B7
     ',', ','    184       ¸            U+00B8
     ''', ','    184       ¸            U+00B8
     '1', '1'    185       ¹            U+00B9
     '1', 'S'    185       ¹            U+00B9
     'o', '-'    186       º            U+00BA
     '>', '>'    187       »            U+00BB
     '1', '4'    188       ¼            U+00BC
     '1', '2'    189       ½            U+00BD
     '3', '4'    190       ¾            U+00BE
     '~', '?'    191       ¿            U+00BF
     '?', '?'    191       ¿            U+00BF
     '?', 'I'    191       ¿            U+00BF
     'A', '`'    192       À            U+00C0
     'A', '!'    192       À            U+00C0
     'A', '''    193       Á            U+00C1
     'A', '^'    194       Â            U+00C2
     'A', '>'    194       Â            U+00C2
     'A', '~'    195       Ã            U+00C3
     'A', '?'    195       Ã            U+00C3
     'A', '"'    196       Ä            U+00C4
     'A', ':'    196       Ä            U+00C4
     'A', '@'    197       Å            U+00C5
     'A', 'A'    197       Å            U+00C5
     'A', 'E'    198       Æ            U+00C6
     'C', ','    199       Ç            U+00C7
     'E', '`'    200       È            U+00C8
     'E', '!'    200       È            U+00C8
     'E', '''    201       É            U+00C9
     'E', '^'    202       Ê            U+00CA
     'E', '>'    202       Ê            U+00CA
     'E', '"'    203       Ë            U+00CB
     'E', ':'    203       Ë            U+00CB
     'I', '`'    204       Ì            U+00CC
     'I', '!'    204       Ì            U+00CC
     'I', '''    205       Í            U+00CD
     'I', '^'    206       Î            U+00CE
     'I', '>'    206       Î            U+00CE
     'I', '"'    207       Ï            U+00CF
     'I', ':'    207       Ï            U+00CF
     'D', '-'    208       Ð            U+00D0
     'N', '~'    209       Ñ            U+00D1
     'N', '?'    209       Ñ            U+00D1
     'O', '`'    210       Ò            U+00D2
     'O', '!'    210       Ò            U+00D2
     'O', '''    211       Ó            U+00D3
     'O', '^'    212       Ô            U+00D4
     'O', '>'    212       Ô            U+00D4
     'O', '~'    213       Õ            U+00D5
     'O', '?'    213       Õ            U+00D5
     'O', '"'    214       Ö            U+00D6
     'O', ':'    214       Ö            U+00D6
     '/', '\'    215       ×            U+00D7
     '*', 'x'    215       ×            U+00D7
     'O', '/'    216       Ø            U+00D8
     'U', '`'    217       Ù            U+00D9
     'U', '!'    217       Ù            U+00D9
     'U', '''    218       Ú            U+00DA
     'U', '^'    219       Û            U+00DB
     'U', '>'    219       Û            U+00DB
     'U', '"'    220       Ü            U+00DC
     'U', ':'    220       Ü            U+00DC
     'Y', '''    221       Ý            U+00DD
     'I', 'p'    222       Þ            U+00DE
     'T', 'H'    222       Þ            U+00DE
     's', 's'    223       ß            U+00DF
     's', '"'    223       ß            U+00DF
     'a', '`'    224       à            U+00E0
     'a', '!'    224       à            U+00E0
     'a', '''    225       á            U+00E1
     'a', '^'    226       â            U+00E2
     'a', '>'    226       â            U+00E2
     'a', '~'    227       ã            U+00E3
     'a', '?'    227       ã            U+00E3
     'a', '"'    228       ä            U+00E4
     'a', ':'    228       ä            U+00E4
     'a', 'a'    229       å            U+00E5
     'a', 'e'    230       æ            U+00E6
     'c', ','    231       ç            U+00E7
     'e', '`'    232       è            U+00E8
     'e', '!'    232       è            U+00E8
     'e', '''    233       é            U+00E9
     'e', '^'    234       ê            U+00EA
     'e', '>'    234       ê            U+00EA
     'e', '"'    235       ë            U+00EB
     'e', ':'    235       ë            U+00EB
     'i', '`'    236       ì            U+00EC
     'i', '!'    236       ì            U+00EC
     'i', '''    237       í            U+00ED
     'i', '^'    238       î            U+00EE
     'i', '>'    238       î            U+00EE
     'i', '"'    239       ï            U+00EF
     'i', ':'    239       ï            U+00EF
     'd', '-'    240       ð            U+00F0
     'n', '~'    241       ñ            U+00F1
     'n', '?'    241       ñ            U+00F1
     'o', '`'    242       ò            U+00F2
     'o', '!'    242       ò            U+00F2
     'o', '''    243       ó            U+00F3
     'o', '^'    244       ô            U+00F4
     'o', '>'    244       ô            U+00F4
     'o', '~'    245       õ            U+00F5
     'o', '?'    245       õ            U+00F5
     'o', '"'    246       ö            U+00F6
     'o', ':'    246       ö            U+00F6
     ':', '-'    247       ÷            U+00F7
     'o', '/'    248       ø            U+00F8
     'u', '`'    249       ù            U+00F9
     'u', '!'    249       ù            U+00F9
     'u', '''    250       ú            U+00FA
     'u', '^'    251       û            U+00FB
     'u', '>'    251       û            U+00FB
     'u', '"'    252       ü            U+00FC
     'u', ':'    252       ü            U+00FC
     'y', '''    253       ý            U+00FD
     'i', 'p'    254       þ            U+00FE
     't', 'h'    254       þ            U+00FE
     'y', '"'    255       ÿ            U+00FF
     'y', ':'    255       ÿ            U+00FF
     '"', '['    196       Ä            U+00C4
     '"', '\'    214       Ö            U+00D6
     '"', ']'    220       Ü            U+00DC
     '"', '{'    228       ä            U+00E4
     '"', '|'    246       ö            U+00F6
     '"', '}'    252       ü            U+00FC
     '"', '~'    223       ß            U+00DF

11.4 Bell ¶

Command: bell_msg [message] ¶

(none)
When a bell character is sent to a background window, screen displays a notification in the message line. The notification message can be re-defined by this command. Each occurrence of ‘%’ in message is replaced by the number of the window to which a bell has been sent, and each occurrence of ‘^G’ is replaced by the definition for bell in your termcap (usually an audible bell). The default message is

'Bell in window %n'

An empty message can be supplied to the bell_msg command to suppress output of a message line (bell_msg ""). Without a parameter, the current message is shown.

Command: vbell [state] ¶

(C-a C-g)
Sets or toggles the visual bell setting for the current window. If vbell is switched to ‘on’, but your terminal does not support a visual bell, the visual bell message is displayed in the status line when the bell character is received. Visual bell support of a terminal is defined by the termcap variable vb. See Bell, for more information on visual bells. The equivalent terminfo capability is flash.

Per default, vbell is ‘off’, thus the audible bell is used.

Command: vbell_msg [message] ¶

(none)
Sets the visual bell message. Message is printed to the status line if the window receives a bell character (^G), vbell is set to ‘on’ and the terminal does not support a visual bell. The default message is ‘Wuff, Wuff!!’. Without a parameter, the current message is shown.

Command: vbellwait sec ¶

(none)
Define a delay in seconds after each display of screen ’s visual bell message. The default is 1 second.

11.5 Clear ¶

Command: clear ¶

(C-a C)
Clears the screen and saves its contents to the scrollback buffer.

11.6 Info ¶

Command: info ¶

(C-a i, C-a C-i)
Uses the message line to display some information about the current window: the cursor position in the form ‘(column,row)’ starting with ‘(1,1)’, the terminal width and height plus the size of the scrollback buffer in lines, like in ‘(80,24)+50’, the current state of window XON/XOFF flow control is shown like this (see Flow Control):

  +flow     automatic flow control, currently on.
  -flow     automatic flow control, currently off.
  +(+)flow  flow control enabled. Agrees with automatic control.
  -(+)flow  flow control disabled. Disagrees with automatic control.
  +(-)flow  flow control enabled. Disagrees with automatic control.
  -(-)flow  flow control disabled. Agrees with automatic control.

The current line wrap setting (‘+wrap’ indicates enabled, ‘-wrap’ not) is also shown. The flags ‘ins’, ‘org’, ‘app’, ‘log’, ‘mon’ and ‘nored’ are displayed when the window is in insert mode, origin mode, application-keypad mode, has output logging, activity monitoring or partial redraw enabled.

The currently active character set (‘G0’, ‘G1’, ‘G2’, or ‘G3’), and in square brackets the terminal character sets that are currently designated as ‘G0’ through ‘G3’. If the window is in UTF-8 mode, the string ‘UTF-8’ is shown instead. Additional modes depending on the type of the window are displayed at the end of the status line (see Window Types).

If the state machine of the terminal emulator is in a non-default state, the info line is started with a string identifying the current state.

For system information use time.

Command: dinfo ¶

(none)
Show what screen thinks about your terminal. Useful if you want to know why features like color or the alternate charset don’t work.

11.7 Redisplay ¶

Command: allpartial state ¶

(none)
If set to on, only the current cursor line is refreshed on window change. This affects all windows and is useful for slow terminal lines. The previous setting of full/partial refresh for each window is restored with allpartial off. This is a global flag that immediately takes effect on all windows overriding the partial settings. It does not change the default redraw behavior of newly created windows.

Command: altscreen state ¶

(none)
If set to on, "alternate screen" support is enabled in virtual terminals, just like in xterm. Initial setting is ‘off’.

Command: partial state ¶

(none)
Defines whether the display should be refreshed (as with redisplay) after switching to the current window. This command only affects the current window. To immediately affect all windows use the allpartial command. Default is ‘off’, of course. This default is fixed, as there is currently no defpartial command.

Command: redisplay ¶

(C-a l, C-a C-l)
Redisplay the current window. Needed to get a full redisplay in partial redraw mode.

11.8 Wrap ¶

Command: wrap [ on | off ] ¶

(C-a r, C-a C-r)
Sets the line-wrap setting for the current window. When line-wrap is on, the second consecutive printable character output at the last column of a line will wrap to the start of the following line. As an added feature, backspace (^H) will also wrap through the left margin to the previous line. Default is ‘on’. Without any options, the state of wrap is toggled.

Command: defwrap state ¶

(none)
Same as the wrap command except that the default setting for new windows is changed. Initially line-wrap is on and can be toggled with the wrap command (C-a r) or by means of "C-a : wrap on|off".

11.9 Reset ¶

Command: reset ¶

(C-a Z)
Reset the virtual terminal to its “power-on” values. Useful when strange settings (like scroll regions or graphics character set) are left over from an application.

11.10 Window Size ¶

Command: width [-w|-d] [cols [lines]] ¶

(C-a W)
Toggle the window width between 80 and 132 columns, or set it to cols columns if an argument is specified. This requires a capable terminal and the termcap entries ‘Z0’ and ‘Z1’. See the termcap command (see Termcap), for more information. You can also specify a height if you want to change both values. The -w option tells screen to leave the display size unchanged and just set the window size, -d vice versa.

Command: height [-w|-d] [lines [cols]] ¶

(none)
Set the display height to a specified number of lines. When no argument is given it toggles between 24 and 42 lines display.

11.11 Character Processing ¶

Command: c1 [state] ¶

(none)
Change c1 code processing. ‘c1 on’ tells screen to treat the input characters between 128 and 159 as control functions. Such an 8-bit code is normally the same as ESC followed by the corresponding 7-bit code. The default setting is to process c1 codes and can be changed with the ‘defc1’ command. Users with fonts that have usable characters in the c1 positions may want to turn this off.

Command: gr [state] ¶

(none)
Turn GR charset switching on/off. Whenever screen sees an input char with an 8th bit set, it will use the charset stored in the GR slot and print the character with the 8th bit stripped. The default (see also ‘defgr’) is not to process GR switching because otherwise the ISO88591 charset would not work.

Command: bce [state] ¶

(none)
Change background-color-erase setting. If ‘bce’ is set to on, all characters cleared by an erase/insert/scroll/clear operation will be displayed in the current background color. Otherwise the default background color is used.

Command: encoding enc [denc] ¶

(none)
Tell screen how to interpret the input/output. The first argument sets the encoding of the current window. Each window can emulate a different encoding. The optional second parameter overwrites the encoding of the connected terminal. It should never be needed as screen uses the locale setting to detect the encoding. There is also a way to select a terminal encoding depending on the terminal type by using the ‘KJ’ termcap entry. See Special Terminal Capabilities.

Supported encodings are eucJP, SJIS, eucKR, eucCN, Big5, GBK, KOI8-R, CP1251, UTF-8, ISO8859-2, ISO8859-3, ISO8859-4, ISO8859-5, ISO8859-6, ISO8859-7, ISO8859-8, ISO8859-9, ISO8859-10, ISO8859-15, jis.

See also ‘defencoding’, which changes the default setting of a new window.

Command: charset set ¶

(none)
Change the current character set slot designation and charset mapping. The first four character of set are treated as charset designators while the fifth and sixth character must be in range ‘0’ to ‘3’ and set the GL/GR charset mapping. On every position a ‘.’ may be used to indicate that the corresponding charset/mapping should not be changed (set is padded to six characters internally by appending ‘.’ chars). New windows have ‘BBBB02’ as default charset, unless a ‘encoding’ command is active.

The current setting can be viewed with the Info command.

Command: utf8 [state [dstate]] ¶

(none)
Change the encoding used in the current window. If utf8 is enabled, the strings sent to the window will be UTF-8 encoded and vice versa. Omitting the parameter toggles the setting. If a second parameter is given, the display’s encoding is also changed (this should rather be done with screen’s ‘-U’ option). See also ‘defutf8’, which changes the default setting of a new window.

Command: defc1 state ¶

(none)
Same as the ‘c1’ command except that the default setting for new windows is changed. Initial setting is ‘on’.

Command: defgr state ¶

(none)
Same as the ‘gr’ command except that the default setting for new windows is changed. Initial setting is ‘off’.

Command: defbce state ¶

(none)
Same as the ‘bce’ command except that the default setting for new windows is changed. Initial setting is ‘off’.

Command: defencoding enc ¶

(none)
Same as the ‘encoding’ command except that the default setting for new windows is changed. Initial setting is the encoding taken from the terminal.

Command: defcharset [set] ¶

(none)
Like the ‘charset’ command except that the default setting for new windows is changed. Shows current default if called without argument.

Command: defutf8 state ¶

(none)
Same as the ‘utf8’ command except that the default setting for new windows is changed. Initial setting is on if screen was started with ‘-U’, otherwise off.

Command: cjkwidth [state] ¶

(none)
Toggle how ambiguous characters are treated. If cjkwidth is on screen interprets them as double (full) width characters. If off then they are seen as one cell (half) width characters.

12.1 Copying ¶

Command: copy ¶

(C-a [, C-a C-[, C-a ESC)
Enter copy/scrollback mode. This allows you to copy text from the current window and its history into the paste buffer. In this mode a vi-like full screen editor is active, with controls as outlined below.

• CR/LF
• Scrollback
• Markkeys
• Movement Keys
• Marking
• Repeat Count
• Searching
• Specials

C-a C-[ H 10 j 5 Y

C-a [ M 20 l SPACE c 10 l 5 j C SPACE.

C-a [ M 20 l SPACE 10 l 5 j SPACE

C-a [ g SPACE G $ >.

12.2 Paste ¶

Command: paste [registers [destination]] ¶

(C-a ], C-a C-])
Write the (concatenated) contents of the specified registers to the stdin stream of the current window. The register ‘.’ is treated as the paste buffer. If no parameter is specified the user is prompted to enter a single register. The paste buffer can be filled with the copy, history and readbuf commands. Other registers can be filled with the register, readreg and paste commands. If paste is called with a second argument, the contents of the specified registers is pasted into the named destination register rather than the window. If ‘.’ is used as the second argument, the display’s paste buffer is the destination. Note, that paste uses a wide variety of resources: Usually both, a current window and a current display are required. But whenever a second argument is specified no current window is needed. When the source specification only contains registers (not the paste buffer) then there need not be a current display (terminal attached), as the registers are a global resource. The paste buffer exists once for every user.

Command: stuff [string] ¶

(none)
Stuff the string string in the input buffer of the current window. This is like the paste command, but with much less overhead. Without a parameter, screen will prompt for a string to stuff. You cannot paste large buffers with the stuff command. It is most useful for key bindings. See Bindkey.

Command: pastefont [state] ¶

Tell screen to include font information in the paste buffer. The default is not to do so. This command is especially useful for multi character fonts like kanji.

Command: slowpaste msec ¶

Command: defslowpaste msec ¶

(none)
Define the speed text is inserted in the current window by the paste command. If the slowpaste value is nonzero text is written character by character. screen will pause for msec milliseconds after each write to allow the application to process the input. only use slowpaste if your underlying system exposes flow control problems while pasting large amounts of text. defslowpaste specifies the default for new windows.

Command: readreg [-e encoding] [register [filename]] ¶

(none)
Does one of two things, dependent on number of arguments: with zero or one arguments it duplicates the paste buffer contents into the register specified or entered at the prompt. With two arguments it reads the contents of the named file into the register, just as readbuf reads the screen-exchange file into the paste buffer. You can tell screen the encoding of the file via the -e option. The following example will paste the system’s password file into the screen window (using register p, where a copy remains):

C-a : readreg p /etc/passwd
C-a : paste p

12.3 Registers ¶

Command: copy_reg [key] ¶

(none)
Removed. Use readreg instead.

Command: ins_reg [key] ¶

(none)
Removed. Use paste instead.

Command: process [key] ¶

(none)
Stuff the contents of the specified register into the screen input queue. If no argument is given you are prompted for a register name. The text is parsed as if it had been typed in from the user’s keyboard. This command can be used to bind multiple actions to a single key.

Command: register [-e encoding] key string ¶

(none)
Save the specified string to the register key. The encoding of the string can be specified via the -e option.

12.4 Screen Exchange ¶

Command: bufferfile [exchange-file] ¶

(none)
Change the filename used for reading and writing with the paste buffer. If the exchange-file parameter is omitted, screen reverts to the default of /tmp/screen-exchange. The following example will paste the system’s password file into the screen window (using the paste buffer, where a copy remains):

C-a : bufferfile /etc/passwd
C-a < C-a ]
C-a : bufferfile

Command: readbuf [-e encoding] [filename] ¶

(C-a <)
Reads the contents of the specified file into the paste buffer. You can tell screen the encoding of the file via the -e option. If no file is specified, the screen-exchange filename is used.

Command: removebuf ¶

(C-a =)
Unlinks the screen-exchange file.

Command: writebuf [-e encoding] [filename] ¶

(C-a >)
Writes the contents of the paste buffer to the specified file, or the public accessible screen-exchange file if no filename is given. This is thought of as a primitive means of communication between screen users on the same host. If an encoding is specified the paste buffer is recoded on the fly to match the encoding. See also C-a ESC (see Copying).

12.5 History ¶

Command: history ¶

(C-a {, C-a })
Usually users work with a shell that allows easy access to previous commands. For example, csh has the command !! to repeat the last command executed. screen provides a primitive way of recalling “the command that started …”: You just type the first letter of that command, then hit C-a { and screen tries to find a previous line that matches with the prompt character to the left of the cursor. This line is pasted into this window’s input queue. Thus you have a crude command history (made up by the visible window and its scrollback buffer).

13.1 Exec ¶

Command: exec [[fdpat] newcommand [args ... ]] ¶

(none)
Run a unix subprocess (specified by an executable path newcommand and its optional arguments) in the current window. The flow of data between newcommands stdin/stdout/stderr, the process originally started (let us call it "application-process") and screen itself (window) is controlled by the file descriptor pattern fdpat. This pattern is basically a three character sequence representing stdin, stdout and stderr of newcommand. A dot (.) connects the file descriptor to screen. An exclamation mark (!) causes the file descriptor to be connected to the application-process. A colon (:) combines both.
User input will go to newcommand unless newcommand receives the application-process’ output (fdpats first character is ‘!’ or ‘:’) or a pipe symbol (‘|’) is added to the end of fdpat.
Invoking exec without arguments shows name and arguments of the currently running subprocess in this window. Only one subprocess can be running per window.
When a subprocess is running the kill command will affect it instead of the windows process. Only one subprocess a time can be running in each window.
Refer to the postscript file doc/fdpat.ps for a confusing illustration of all 21 possible combinations. Each drawing shows the digits 2, 1, 0 representing the three file descriptors of newcommand. The box marked ‘W’ is usual pty that has the application-process on its slave side. The box marked ‘P’ is the secondary pty that now has screen at its master side.

13.2 Using Exec ¶

Abbreviations:

• Whitespace between the word ‘exec’ and fdpat and the command name can be omitted.
• Trailing dots and a fdpat consisting only of dots can be omitted.
• A simple ‘|’ is synonymous for the ‘!..|’ pattern.
• The word ‘exec’ can be omitted when the ‘|’ abbreviation is used.
• The word ‘exec’ can always be replaced by leading ‘!’.

Examples:

!/bin/sh

exec /bin/sh

exec ... /bin/sh

All of the above are equivalent. Creates another shell in the same window, while the original shell is still running. Output of both shells is displayed and user input is sent to the new /bin/sh.

!!stty 19200

exec!stty 19200

exec !.. stty 19200

All of the above are equivalent. Set the speed of the window’s tty. If your stty command operates on stdout, then add another ‘!’. This is a useful command, when a screen window is directly connected to a serial line that needs to be configured.

|less

exec !..| less

Both are equivalent. This adds a pager to the window output. The special character ‘|’ is needed to give the user control over the pager although it gets its input from the window’s process. This works, because ‘less’ listens on stderr (a behavior that screen would not expect without the ‘|’) when its stdin is not a tty. Less versions newer than 177 fail miserably here; good old pg still works.

!:sed -n s/.*Error.*/\007/p

Sends window output to both, the user and the sed command. The sed inserts an additional bell character (oct. 007) to the window output seen by screen. This will cause ’Bell in window x’ messages, whenever the string ‘Error’ appears in the window.

14.1 The bind command ¶

Command: bind [-c class] key [command [args]] ¶

(none)
Bind a command to a key. The key argument is either a single character, a two-character sequence of the form ‘^x’ (meaning C-x), a backslash followed by an octal number (specifying the ASCII code of the character), or a backslash followed by a second character, such as ‘\^’ or ‘\\’. The argument can also be quoted, if you like. If no further argument is given, any previously established binding for this key is removed. The command argument can be any command (see Command Index).

If a command class is specified via the -c option, the key is bound for the specified class. Use the command command to activate a class. Command classes can be used to create multiple command keys or multi-character bindings.

By default, most suitable commands are bound to one or more keys (see Default Key Bindings); for instance, the command to create a new window is bound to C-c and c. The bind command can be used to redefine the key bindings and to define new bindings.

Command: unbindall ¶

(none)
Unbind all the bindings. This can be useful when screen is used solely for its detaching abilities, such as when letting a console application run as a daemon. If, for some reason, it is necessary to bind commands after this, use ’screen -X’.

14.2 Examples of the bind command ¶

Some examples:

bind ' ' windows
bind ^f screen telnet foobar
bind \033 screen -ln -t root -h 1000 9 su

would bind the space key to the command that displays a list of windows (so that the command usually invoked by C-a C-w would also be available as C-a space), bind C-f to the command “create a window with a TELNET connection to foobar”, and bind ESC to the command that creates an non-login window with title ‘root’ in slot #9, with a superuser shell and a scrollback buffer of 1000 lines.

bind -c demo1 0 select 10
bind -c demo1 1 select 11
bind -c demo1 2 select 12
bindkey "^B" command -c demo1

makes C-b 0 select window 10, C-b 1 window 11, etc.

bind -c demo2 0 select 10
bind -c demo2 1 select 11
bind -c demo2 2 select 12
bind - command -c demo2

makes C-a - 0 select window 10, C-a - 1 window 11, etc.

14.3 Command Character ¶

Command: escape xy ¶

(none)
Set the command character to x and the character generating a literal command character (by triggering the meta command) to y (similar to the ‘-e’ option). Each argument is either a single character, a two-character sequence of the form ‘^x’ (meaning C-x), a backslash followed by an octal number (specifying the ASCII code of the character), or a backslash followed by a second character, such as ‘\^’ or ‘\\’. The default is ‘^Aa’, but ‘``’ is recommended by one of the authors.

Command: defescape xy ¶

(none)
Set the default command characters. This is equivalent to the command escape except that it is useful for multiuser sessions only. In a multiuser session escape changes the command character of the calling user, where defescape changes the default command characters for users that will be added later.

Command: meta ¶

(C-a a)
Send the command character (C-a) to the process in the current window. The keystroke for this command is the second parameter to the ‘-e’ command line switch (see Invoking Screen), or the escape .screenrc directive.

Command: command [-c class] ¶

(none)
This command has the same effect as typing the screen escape character (C-a). It is probably only useful for key bindings. If the ‘-c’ option is given, select the specified command class. See The bind command, See Bindkey.

14.4 Help ¶

Command: help ¶

(C-a ?)
Displays a help screen showing you all the key bindings. The first pages list all the internal commands followed by their bindings. Subsequent pages will display the custom commands, one command per key. Press space when you’re done reading each page, or return to exit early. All other characters are ignored. If the ‘-c’ option is given, display all bound commands for the specified command class. See Default Key Bindings.

14.5 Bindkey ¶

Command: bindkey [opts] [string [cmd args]] ¶

(none)
This command manages screen’s input translation tables. Every entry in one of the tables tells screen how to react if a certain sequence of characters is encountered. There are three tables: one that should contain actions programmed by the user, one for the default actions used for terminal emulation and one for screen’s copy mode to do cursor movement. See Input Translation for a list of default key bindings.

If the ‘-d’ option is given, bindkey modifies the default table, ‘-m’ changes the copy mode table and with neither option the user table is selected. The argument ‘string’ is the sequence of characters to which an action is bound. This can either be a fixed string or a termcap keyboard capability name (selectable with the ‘-k’ option).

Some keys on a VT100 terminal can send a different string if application mode is turned on (e.g. the cursor keys). Such keys have two entries in the translation table. You can select the application mode entry by specifying the ‘-a’ option.

The ‘-t’ option tells screen not to do inter-character timing. One cannot turn off the timing if a termcap capability is used.

‘cmd’ can be any of screen’s commands with an arbitrary number of ‘args’. If ‘cmd’ is omitted the key-binding is removed from the table.

14.6 Bindkey Examples ¶

Here are some examples of keyboard bindings:

bindkey -d

Show all of the default key bindings. The application mode entries are marked with [A].

bindkey -k k1 select 1

Make the "F1" key switch to window one.

bindkey -t foo stuff barfoo

Make ‘foo’ an abbreviation of the word ‘barfoo’. Timeout is disabled so that users can type slowly.

bindkey "\024" mapdefault

This key-binding makes ‘C-t’ an escape character for key-bindings. If you did the above ‘stuff barfoo’ binding, you can enter the word ‘foo’ by typing ‘C-t foo’. If you want to insert a ‘C-t’ you have to press the key twice (i.e., escape the escape binding).

bindkey -k F1 command

Make the F11 (not F1!) key an alternative screen escape (besides ‘C-a’).

14.7 Bindkey Control ¶

Command: mapdefault ¶

(none)
Tell screen that the next input character should only be looked up in the default bindkey table.

Command: mapnotnext ¶

(none)
Like mapdefault, but don’t even look in the default bindkey table.

Command: maptimeout n ¶

(none)
Set the inter-character timer for input sequence detection to a timeout of n ms. The default timeout is 300ms. Maptimeout with no arguments shows the current setting.

15.1 About screen flow control settings ¶

Each window has a flow-control setting that determines how screen deals with the XON and XOFF characters (and perhaps the interrupt character). When flow-control is turned off, screen ignores the XON and XOFF characters, which allows the user to send them to the current program by simply typing them (useful for the emacs editor, for instance). The trade-off is that it will take longer for output from a “normal” program to pause in response to an XOFF. With flow-control turned on, XON and XOFF characters are used to immediately pause the output of the current window. You can still send these characters to the current program, but you must use the appropriate two-character screen commands (typically C-a q (xon) and C-a s (xoff)). The xon/xoff commands are also useful for typing C-s and C-q past a terminal that intercepts these characters.

Each window has an initial flow-control value set with either the ‘-f’ option or the defflow command. By default the windows are set to automatic flow-switching. It can then be toggled between the three states ’fixed on’, ’fixed off’ and ’automatic’ interactively with the flow command bound to C-a f.

The automatic flow-switching mode deals with flow control using the TIOCPKT mode (like rlogin does). If the tty driver does not support TIOCPKT, screen tries to determine the right mode based on the current setting of the application keypad — when it is enabled, flow-control is turned off and visa versa. Of course, you can still manipulate flow-control manually when needed.

If you’re running with flow-control enabled and find that pressing the interrupt key (usually C-c) does not interrupt the display until another 6-8 lines have scrolled by, try running screen with the ‘interrupt’ option (add the ‘interrupt’ flag to the flow command in your .screenrc, or use the ‘-i’ command-line option). This causes the output that screen has accumulated from the interrupted program to be flushed. One disadvantage is that the virtual terminal’s memory contains the non-flushed version of the output, which in rare cases can cause minor inaccuracies in the output. For example, if you switch screens and return, or update the screen with C-a l you would see the version of the output you would have gotten without ‘interrupt’ being on. Also, you might need to turn off flow-control (or use auto-flow mode to turn it off automatically) when running a program that expects you to type the interrupt character as input, as the ‘interrupt’ parameter only takes effect when flow-control is enabled. If your program’s output is interrupted by mistake, a simple refresh of the screen with C-a l will restore it. Give each mode a try, and use whichever mode you find more comfortable.

15.2 Flow ¶

Command: defflow fstate [interrupt] ¶

(none)
Same as the flow command except that the default setting for new windows is changed. Initial setting is ‘auto’. Specifying flow auto interrupt has the same effect as the command-line options ‘-fa’ and ‘-i’. Note that if ‘interrupt’ is enabled, all existing displays are changed immediately to forward interrupt signals.

Command: flow [fstate] ¶

(C-a f, C-a C-f)
Sets the flow-control mode for this window to fstate, which can be ‘on’, ‘off’ or ‘auto’. Without parameters it cycles the current window’s flow-control setting. Default is set by ‘defflow’.

15.3 XON and XOFF ¶

Command: xon ¶

(C-a q, C-a C-q)
Send a ^Q (ASCII XON) to the program in the current window. Redundant if flow control is set to ‘off’ or ‘auto’.

Command: xoff ¶

(C-a s, C-a C-s)
Send a ^S (ASCII XOFF) to the program in the current window.

16.1 Choosing the termcap entry for a window ¶

Usually screen tries to emulate as much of the VT100/ANSI standard as possible. But if your terminal lacks certain capabilities the emulation may not be complete. In these cases screen has to tell the applications that some of the features are missing. This is no problem on machines using termcap, because screen can use the $TERMCAP variable to customize the standard screen termcap.

But if you do a rlogin on another machine or your machine supports only terminfo this method fails. Because of this screen offers a way to deal with these cases. Here is how it works:

When screen tries to figure out a terminal name for itself, it first looks for an entry named screen.term, where term is the contents of your $TERM variable. If no such entry exists, screen tries ‘screen’ (or ‘screen-w’, if the terminal is wide (132 cols or more)). If even this entry cannot be found, ‘vt100’ is used as a substitute.

The idea is that if you have a terminal which doesn’t support an important feature (e.g. delete char or clear to EOS) you can build a new termcap/terminfo entry for screen (named ‘screen.dumbterm’) in which this capability has been disabled. If this entry is installed on your machines you are able to do a rlogin and still keep the correct termcap/terminfo entry. The terminal name is put in the $TERM variable of all new windows. screen also sets the $TERMCAP variable reflecting the capabilities of the virtual terminal emulated. Furthermore, the variable $WINDOW is set to the window number of each window.

The actual set of capabilities supported by the virtual terminal depends on the capabilities supported by the physical terminal. If, for instance, the physical terminal does not support underscore mode, screen does not put the ‘us’ and ‘ue’ capabilities into the window’s $TERMCAP variable, accordingly. However, a minimum number of capabilities must be supported by a terminal in order to run screen; namely scrolling, clear screen, and direct cursor addressing (in addition, screen does not run on hardcopy terminals or on terminals that over-strike).

Also, you can customize the $TERMCAP value used by screen by using the termcap command, or by defining the variable $SCREENCAP prior to startup. When the latter defined, its value will be copied verbatim into each window’s $TERMCAP variable. This can either be the full terminal definition, or a filename where the terminal ‘screen’ (and/or ‘screen-w’) is defined.

Note that screen honors the terminfo command if the system uses the terminfo database rather than termcap. On such machines the $TERMCAP variable has no effect and you must use the dumptermcap command (see Write out the window’s termcap entry) and the tic program to generate terminfo entries for screen windows.

When the boolean ‘G0’ capability is present in the termcap entry for the terminal on which screen has been called, the terminal emulation of screen supports multiple character sets. This allows an application to make use of, for instance, the VT100 graphics character set or national character sets. The following control functions from ISO 2022 are supported: ‘lock shift G0’ (‘SI’), ‘lock shift G1’ (‘SO’), ‘lock shift G2’, ‘lock shift G3’, ‘single shift G2’, and ‘single shift G3’. When a virtual terminal is created or reset, the ASCII character set is designated as ‘G0’ through ‘G3’. When the ‘G0’ capability is present, screen evaluates the capabilities ‘S0’, ‘E0’, and ‘C0’ if present. ‘S0’ is the sequence the terminal uses to enable and start the graphics character set rather than ‘SI’. ‘E0’ is the corresponding replacement for ‘SO’. ‘C0’ gives a character by character translation string that is used during semi-graphics mode. This string is built like the ‘acsc’ terminfo capability.

When the ‘po’ and ‘pf’ capabilities are present in the terminal’s termcap entry, applications running in a screen window can send output to the printer port of the terminal. This allows a user to have an application in one window sending output to a printer connected to the terminal, while all other windows are still active (the printer port is enabled and disabled again for each chunk of output). As a side-effect, programs running in different windows can send output to the printer simultaneously. Data sent to the printer is not displayed in the window. The info command displays a line starting with ‘PRIN’ while the printer is active.

Some capabilities are only put into the $TERMCAP variable of the virtual terminal if they can be efficiently implemented by the physical terminal. For instance, ‘dl’ (delete line) is only put into the $TERMCAP variable if the terminal supports either delete line itself or scrolling regions. Note that this may provoke confusion, when the session is reattached on a different terminal, as the value of $TERMCAP cannot be modified by parent processes. You can force screen to include all capabilities in $TERMCAP with the ‘-a’ command-line option (see Invoking Screen).

The "alternate screen" capability is not enabled by default. Set the altscreen .screenrc command to enable it.

16.2 Write out the window’s termcap entry ¶

Command: dumptermcap ¶

(C-a .)
Write the termcap entry for the virtual terminal optimized for the currently active window to the file .termcap in the user’s $HOME/.screen directory (or wherever screen stores its sockets. see Files Referenced). This termcap entry is identical to the value of the environment variable $TERMCAP that is set up by screen for each window. For terminfo based systems you will need to run a converter like captoinfo and then compile the entry with tic.

16.3 The termcap command ¶

Command: termcap term terminal-tweaks [window-tweaks] ¶

Command: terminfo term terminal-tweaks [window-tweaks] ¶

Command: termcapinfo term terminal-tweaks [window-tweaks] ¶

(none)
Use this command to modify your terminal’s termcap entry without going through all the hassles involved in creating a custom termcap entry. Plus, you can optionally customize the termcap generated for the windows. You have to place these commands in one of the screenrc startup files, as they are meaningless once the terminal emulator is booted.

If your system uses the terminfo database rather than termcap, screen will understand the terminfo command, which has the same effects as the termcap command. Two separate commands are provided, as there are subtle syntactic differences, e.g. when parameter interpolation (using ‘%’) is required. Note that the termcap names of the capabilities should also be used with the terminfo command.

In many cases, where the arguments are valid in both terminfo and termcap syntax, you can use the command termcapinfo, which is just a shorthand for a pair of termcap and terminfo commands with identical arguments.

The first argument specifies which terminal(s) should be affected by this definition. You can specify multiple terminal names by separating them with ‘|’s. Use ‘*’ to match all terminals and ‘vt*’ to match all terminals that begin with ‘vt’.

Each tweak argument contains one or more termcap defines (separated by ‘:’s) to be inserted at the start of the appropriate termcap entry, enhancing it or overriding existing values. The first tweak modifies your terminal’s termcap, and contains definitions that your terminal uses to perform certain functions. Specify a null string to leave this unchanged (e.g. ""). The second (optional) tweak modifies all the window termcaps, and should contain definitions that screen understands (see Virtual Terminal).

16.4 Termcap Examples ¶

Some examples:

termcap xterm*  xn:hs@

Informs screen that all terminals that begin with ‘xterm’ have firm auto-margins that allow the last position on the screen to be updated (xn), but they don’t really have a status line (no ’hs’ – append ‘@’ to turn entries off). Note that we assume ‘xn’ for all terminal names that start with ‘vt’, but only if you don’t specify a termcap command for that terminal.

termcap vt*  xn
termcap vt102|vt220  Z0=\E[?3h:Z1=\E[?3l

Specifies the firm-margined ‘xn’ capability for all terminals that begin with ‘vt’, and the second line will also add the escape-sequences to switch into (Z0) and back out of (Z1) 132-character-per-line mode if this is a VT102 or VT220. (You must specify Z0 and Z1 in your termcap to use the width-changing commands.)

termcap vt100  ""  l0=PF1:l1=PF2:l2=PF3:l3=PF4

This leaves your vt100 termcap alone and adds the function key labels to each window’s termcap entry.

termcap h19|z19  am@:im=\E@:ei=\EO  dc=\E[P

Takes a h19 or z19 termcap and turns off auto-margins (am@) and enables the insert mode (im) and end-insert (ei) capabilities (the ‘@’ in the ‘im’ string is after the ‘=’, so it is part of the string). Having the ‘im’ and ‘ei’ definitions put into your terminal’s termcap will cause screen to automatically advertise the character-insert capability in each window’s termcap. Each window will also get the delete-character capability (dc) added to its termcap, which screen will translate into a line-update for the terminal (we’re pretending it doesn’t support character deletion).

If you would like to fully specify each window’s termcap entry, you should instead set the $SCREENCAP variable prior to running screen. See Virtual Terminal, for the details of the screen terminal emulation. See Termcap, for more information on termcap definitions.

16.5 Special Terminal Capabilities ¶

The following table describes all terminal capabilities that are recognized by screen and are not in the termcap manual (see Termcap). You can place these capabilities in your termcap entries (in /etc/termcap) or use them with the commands termcap, terminfo and termcapinfo in your screenrc files. It is often not possible to place these capabilities in the terminfo database.

‘LP’

(bool)
Terminal has VT100 style margins (‘magic margins’). Note that this capability is obsolete — screen now uses the standard ‘xn’ instead.

‘Z0’

(str)
Change width to 132 columns.

‘Z1’

(str)
Change width to 80 columns.

‘WS’

(str)
Resize display. This capability has the desired width and height as arguments. SunView(tm) example: ‘\E[8;%d;%dt’.

‘NF’

(bool)
Terminal doesn’t need flow control. Send ^S and ^Q direct to the application. Same as flow off. The opposite of this capability is ‘nx’.

‘G0’

(bool)
Terminal can deal with ISO 2022 font selection sequences.

‘S0’

(str)
Switch charset ‘G0’ to the specified charset. Default is ‘\E(%.’.

‘E0’

(str)
Switch charset ‘G0’ back to standard charset. Default is ‘\E(B’.

‘C0’

(str)
Use the string as a conversion table for font 0. See the ‘ac’ capability for more details.

‘CS’

(str)
Switch cursor-keys to application mode.

‘CE’

(str)
Switch cursor-keys to cursor mode.

‘AN’

(bool)
Enable autonuke for displays of this terminal type. (see Autonuke).

‘OL’

(num)
Set the output buffer limit. See the ‘obuflimit’ command (see Obuflimit) for more details.

‘KJ’

(str)
Set the encoding of the terminal. See the ‘encoding’ command (see Character Processing) for valid encodings.

‘AF’

(str)
Change character foreground color in an ANSI conform way. This capability will almost always be set to ‘\E[3%dm’ (‘\E[3%p1%dm’ on terminfo machines).

‘AB’

(str)
Same as ‘AF’, but change background color.

‘AX’

(bool)
Does understand ANSI set default fg/bg color (‘\E[39m / \E[49m’).

‘XC’

(str)
Describe a translation of characters to strings depending on the current font. (see Character Translation).

‘XT’

(bool)
Terminal understands special xterm sequences (OSC, mouse tracking).

‘C8’

(bool)
Terminal needs bold to display high-intensity colors (e.g. Eterm).

‘TF’

(bool)
Add missing capabilities to the termcap/info entry. (Set by default).

16.6 Autonuke ¶

Command: autonuke state ¶

(none)
Sets whether a clear screen sequence should nuke all the output that has not been written to the terminal. See Obuflimit. This property is set per display, not per window.

Command: defautonuke state ¶

(none)
Same as the autonuke command except that the default setting for new displays is also changed. Initial setting is off. Note that you can use the special AN terminal capability if you want to have a terminal type dependent setting.

16.7 Obuflimit ¶

Command: obuflimit [limit] ¶

(none)
If the output buffer contains more bytes than the specified limit, no more data will be read from the windows. The default value is 256. If you have a fast display (like xterm), you can set it to some higher value. If no argument is specified, the current setting is displayed. This property is set per display, not per window.

Command: defobuflimit limit ¶

(none)
Same as the obuflimit command except that the default setting for new displays is also changed. Initial setting is 256 bytes. Note that you can use the special OL terminal capability if you want to have a terminal type dependent limit.

16.8 Character Translation ¶

Screen has a powerful mechanism to translate characters to arbitrary strings depending on the current font and terminal type. Use this feature if you want to work with a common standard character set (say ISO8851-latin1) even on terminals that scatter the more unusual characters over several national language font pages.

Syntax:

    XC=<charset-mapping>{,,<charset-mapping>}
    <charset-mapping> := <designator><template>{,<mapping>}
    <mapping> := <char-to-be-mapped><template-arg>

The things in braces may be repeated any number of times.

A <charset-mapping> tells screen how to map characters in font <designator> (‘B’: Ascii, ‘A’: UK, ‘K’: german, etc.) to strings. Every <mapping> describes to what string a single character will be translated. A template mechanism is used, as most of the time the codes have a lot in common (for example strings to switch to and from another charset). Each occurrence of ‘%’ in <template> gets substituted with the template-arg specified together with the character. If your strings are not similar at all, then use ‘%’ as a template and place the full string in <template-arg>. A quoting mechanism was added to make it possible to use a real ‘%’. The ‘\’ character quotes the special characters ‘\’, ‘%’, and ‘,’.

Here is an example:

    termcap hp700 'XC=B\E(K%\E(B,\304[,\326\\\\,\334]'

This tells screen, how to translate ISOlatin1 (charset ‘B’) upper case umlaut characters on a hp700 terminal that has a German charset. ‘\304’ gets translated to ‘\E(K[\E(B’ and so on. Note that this line gets parsed *three* times before the internal lookup table is built, therefore a lot of quoting is needed to create a single ‘\’.

Another extension was added to allow more emulation: If a mapping translates the unquoted ‘%’ char, it will be sent to the terminal whenever screen switches to the corresponding <designator>. In this special case the template is assumed to be just ‘%’ because the charset switch sequence and the character mappings normally haven’t much in common.

This example shows one use of the extension:

    termcap xterm 'XC=K%,%\E(B,[\304,\\\\\326,]\334'

Here, a part of the German (‘K’) charset is emulated on an xterm. If screen has to change to the ‘K’ charset, ‘\E(B’ will be sent to the terminal, i.e. the ASCII charset is used instead. The template is just ‘%’, so the mapping is straightforward: ‘[’ to ‘\304’, ‘\’ to ‘\326’, and ‘]’ to ‘\334’.

17.1 Using the message line from your program ¶

The message line facility can be used by an application running in the current window by means of the ANSI Privacy message control sequence. For instance, from within the shell, try something like:

echo "{No value for `esc'}^Hello world from window $WINDOW{No value for `esc'}\"

where ‘{No value for `esc'}’ is ASCII ESC and the ‘^’ that follows it is a literal caret or up-arrow.

17.2 Hardware Status Line ¶

Command: hardstatus [state] ¶

Command: hardstatus [always]firstline|lastline|message|ignore [string] ¶

Command: hardstatus string [string] ¶

(none)
This command configures the use and emulation of the terminal’s hardstatus line. The first form toggles whether screen will use the hardware status line to display messages. If the flag is set to ‘off’, these messages are overlaid in reverse video mode at the display line. The default setting is ‘on’.

The second form tells screen what to do if the terminal doesn’t have a hardstatus line (i.e. the termcap/terminfo capabilities "hs", "ts", "fs" and "ds" are not set). If the type firstline/lastline is used, screen will reserve the first/last line of the display for the hardstatus. message uses screen’s message mechanism and ignore tells screen never to display the hardstatus. If you prepend the word always to the type (e.g., alwayslastline), screen will use the type even if the terminal supports a hardstatus line.

The third form specifies the contents of the hardstatus line. %h is used as default string, i.e., the stored hardstatus of the current window (settable via ‘ESC]0;^G’ or ‘ESC_\\’) is displayed. You can customize this to any string you like including string escapes (see String Escapes). If you leave out the argument string, the current string is displayed.

You can mix the second and third form by providing the string as additional argument.

17.3 Display Last Message ¶

Command: lastmsg ¶

(C-a m, C-a C-m)
Repeat the last message displayed in the message line. Useful if you’re typing when a message appears, because (unless your terminal has a hardware status line) the message goes away when you press a key.

17.4 Message Wait ¶

Command: msgminwait sec ¶

(none)
Defines the time screen delays a new message when another is currently displayed. Defaults to 1 second.

Command: msgwait sec ¶

(none)
Defines the time a message is displayed, if screen is not disturbed by other activity. Defaults to 5 seconds.

18.1 hardcopy ¶

Command: hardcopy [-h] [file] ¶

(C-a h)
Writes out the currently displayed image to the file file, or, if no filename is specified, to hardcopy.n in the default directory, where n is the number of the current window. This either appends or overwrites the file if it exists, as determined by the hardcopy_append command. If the option -h is specified, dump also the contents of the scrollback buffer.

Command: hardcopy_append state ¶

(none)
If set to ‘on’, screen will append to the hardcopy.n files created by the command hardcopy; otherwise, these files are overwritten each time.

Command: hardcopydir directory ¶

(none)
Defines a directory where hardcopy files will be placed. If unset, hardcopys are dumped in screen’s current working directory.

18.2 log ¶

Command: deflog state ¶

(none)
Same as the log command except that the default setting for new windows is changed. Initial setting is ‘off’.

Command: log [state] ¶

(C-a H)
Begins/ends logging of the current window to the file screenlog.n in the window’s default directory, where n is the number of the current window. This filename can be changed with the ‘logfile’ command. If no parameter is given, the logging state is toggled. The session log is appended to the previous contents of the file if it already exists. The current contents and the contents of the scrollback history are not included in the session log. Default is ‘off’.

Command: logfile filename ¶

Command: logfile flush secs ¶

(none)
Defines the name the log files will get. The default is ‘screenlog.%n’. The second form changes the number of seconds screen will wait before flushing the logfile buffer to the file-system. The default value is 10 seconds.

Command: logtstamp [state] ¶

Command: logtstamp after secs ¶

Command: logtstamp string string ¶

(none)
This command controls logfile time-stamp mechanism of screen. If time-stamps are turned ‘on’, screen adds a string containing the current time to the logfile after two minutes of inactivity. When output continues and more than another two minutes have passed, a second time-stamp is added to document the restart of the output. You can change this timeout with the second form of the command. The third form is used for customizing the time-stamp string (‘-- %n:%t -- time-stamp -- %M/%d/%y %c:%s --\n’ by default).

19.1 echo ¶

Command: echo [‘-n’] message ¶

(none)
The echo command may be used to annoy screen users with a ’message of the day’. Typically installed in a global screenrc. The option ‘-n’ may be used to suppress the line feed. See also sleep. Echo is also useful for online checking of environment variables.

19.2 sleep ¶

Command: sleep num ¶

(none)
This command will pause the execution of a .screenrc file for num seconds. Keyboard activity will end the sleep. It may be used to give users a chance to read the messages output by echo.

19.3 Startup Message ¶

Command: startup_message state ¶

(none)
Select whether you want to see the copyright notice during startup. Default is ‘on’, as you probably noticed.

20.1 At ¶

Command: at [identifier][#|*|%] command [args] ¶

(none)
Execute a command at other displays or windows as if it had been entered there. At changes the context (the ‘current window’ or ‘current display’ setting) of the command. If the first parameter describes a non-unique context, the command will be executed multiple times. If the first parameter is of the form ‘identifier*’ then identifier is matched against user names. The command is executed once for each display of the selected user(s). If the first parameter is of the form ‘identifier%’ identifier is matched against displays. Displays are named after the ttys they attach. The prefix ‘/dev/’ or ‘/dev/tty’ may be omitted from the identifier. If identifier has a # or nothing appended it is matched against window numbers and titles. Omitting an identifier in front of the #, * or % character selects all users, displays or windows because a prefix-match is performed. Note that on the affected display(s) a short message will describe what happened. Note that the # character works as a comment introducer when it is preceded by whitespace. This can be escaped by prefixing # with a \. Permission is checked for the initiator of the at command, not for the owners of the affected display(s). Caveat: When matching against windows, the command is executed at least once per window. Commands that change the internal arrangement of windows (like other) may be called again. In shared windows the command will be repeated for each attached display. Beware, when issuing toggle commands like login! Some commands (e.g. \*Qprocess) require that a display is associated with the target windows. These commands may not work correctly under at looping over windows.

20.2 Break ¶

Command: break [duration] ¶

(C-a b, C-a C-b)
Send a break signal for duration*0.25 seconds to this window. For non-Posix systems the time interval is rounded up to full seconds. Most useful if a character device is attached to the window rather than a shell process (see Window Types). The maximum duration of a break signal is limited to 15 seconds.

Command: pow_break ¶

(C-a B)
Reopen the window’s terminal line and send a break condition.

Command: breaktype [tcsendbreak|TIOCSBRK|TCSBRK] ¶

(none)
Choose one of the available methods of generating a break signal for terminal devices. This command should affect the current window only. But it still behaves identical to defbreaktype. This will be changed in the future. Calling breaktype with no parameter displays the break setting for the current window.

Command: defbreaktype [tcsendbreak|TIOCSBRK|TCSBRK] ¶

(none)
Choose one of the available methods of generating a break signal for terminal devices opened afterwards. The preferred methods are tcsendbreak and TIOCSBRK. The third, TCSBRK, blocks the complete screen session for the duration of the break, but it may be the only way to generate long breaks. tcsendbreak and TIOCSBRK may or may not produce long breaks with spikes (e.g. 4 per second). This is not only system dependent, this also differs between serial board drivers. Calling defbreaktype with no parameter displays the current setting.

20.3 Bumpleft ¶

Command: bumpleft ¶

(none)
Exchanges windows positions on window list, with window having lower number (left to current one).

20.4 Bumpright ¶

Command: bumpright ¶

(none)
Exchanges windows positions on window list, with window having bigger number (right to current one).

20.5 Collapse ¶

Command: collapse ¶

(none)
Changes windows numbers, so there is no gaps between them.

20.6 Debug ¶

Command: debug [on|off] ¶

(none)
Turns runtime debugging on or off. If screen has been compiled with option -DDEBUG debugging is available and is turned on per default. Note that this command only affects debugging output from the main ‘SCREEN’ process correctly. Debug output from attacher processes can only be turned off once and forever.

20.7 License ¶

Command: license ¶

(C-a ,)
Display the disclaimer page. This is done whenever screen is started without options, which should be often enough.

20.8 Nethack ¶

Command: nethack state ¶

(none)
Changes the kind of error messages used by screen. When you are familiar with the game nethack, you may enjoy the nethack-style messages which will often blur the facts a little, but are much funnier to read. Anyway, standard messages often tend to be unclear as well.

This option is only available if screen was compiled with the NETHACK flag defined (see Installation). The default setting is then determined by the presence of the environment variable $NETHACKOPTIONS and the file ~/.nethackrc - if either one is present, the default is on.

20.9 Nonblock ¶

Command: nonblock [state|numsecs] ¶

Tell screen how to deal with user interfaces (displays) that cease to accept output. This can happen if a user presses ^S or a TCP/modem connection gets cut but no hangup is received. If nonblock is off (this is the default) screen waits until the display restarts to accept the output. If nonblock is on, screen waits until the timeout is reached (on is treated as 1s). If the display still doesn’t receive characters, screen will consider it “blocked” and stop sending characters to it. If at some time it restarts to accept characters, screen will unblock the display and redisplay the updated window contents.

Command: defnonblock state|numsecs ¶

Same as the nonblock command except that the default setting for displays is changed. Initial setting is off.

20.10 Number ¶

Command: number [[+|-]n] ¶

(C-a N)
Change the current window’s number. If the given number n is already used by another window, both windows exchange their numbers. If no argument is specified, the current window number (and title) is shown. Using either a plus (‘+’) or minus (‘-’) will change the window’s number by the relative amount specified.

20.11 Time ¶

Command: time [string] ¶

(C-a t, C-a C-t)
Uses the message line to display the time of day, the host name, and the load averages over 1, 5, and 15 minutes (if this is available on your system). For window-specific information use info (see Info). If a string is specified, it changes the format of the time report like it is described in the string escapes chapter (see String Escapes). Screen uses a default of ‘%c:%s %M %d %H%? %l%?’.

20.12 Verbose ¶

Command: verbose [on|off] ¶

If verbose is switched on, the command name is echoed, whenever a window is created (or resurrected from zombie state). Default is off. Without a parameter, the current setting is shown.

20.13 Version ¶

Command: version ¶

(C-a v)
Display the version and modification date in the message line.

20.14 Zombie ¶

Command: zombie [keys [onerror] ] ¶

Command: zombie_timeout [seconds] ¶

(none)
Per default windows are removed from the window list as soon as the windows process (e.g. shell) exits. When a string of two keys is specified to the zombie command, ‘dead’ windows will remain in the list. The kill command may be used to remove the window. Pressing the first key in the dead window has the same effect. Pressing the second key, however, screen will attempt to resurrect the window. The process that was initially running in the window will be launched again. Calling zombie without parameters will clear the zombie setting, thus making windows disappear when the process terminates.

As the zombie setting is affected globally for all windows, this command should probably be called defzombie, but it isn’t.

Optionally you can put the word onerror after the keys. This will cause screen to monitor exit status of the process running in the window. If it exits normally (’0’), the window disappears. Any other exit value causes the window to become a zombie.

Additionally the zombie_timeout command exists. If a window is declared “dead”, screen will automatically try to resurrect the window after the timeout. It only works if zombie keys are defined via zombie command.

20.15 Printcmd ¶

Command: printcmd [cmd] ¶

(none)
If cmd is not an empty string, screen will not use the terminal capabilities po/pf for printing if it detects an ansi print sequence ESC [ 5 i, but pipe the output into cmd. This should normally be a command like ‘lpr’ or ‘cat > /tmp/scrprint’. Printcmd without an argument displays the current setting. The ansi sequence ESC [ 4 i ends printing and closes the pipe.

Warning: Be careful with this command! If other user have write access to your terminal, they will be able to fire off print commands.

20.16 Rendition ¶

Command: rendition bell | monitor | silence | so attr [color] ¶

(none)
Change the way screen renders the titles of windows that have monitor or bell flags set in caption or hardstatus or windowlist. See the chapter about string escapes (see String Escapes) for the syntax of the modifiers. The default for monitor is currently ‘=b’ (bold, active colors), for bell ‘=ub’ (underline, bold and active colors), and for silence ‘=u’.

20.17 Sorendition ¶

Command: sorendition [attr [color]] ¶

(none)
This command has been deprecated. Use rendition so instead.

20.18 Attrcolor ¶

Command: attrcolor attrib [attribute/color-modifier] ¶

(none)
This command can be used to highlight attributes by changing the color of the text. If the attribute attrib is in use, the specified attribute/color modifier is also applied. If no modifier is given, the current one is deleted. See the chapter about string escapes (see String Escapes) for the syntax of the modifier. Screen understands two pseudo-attributes, i stands for high-intensity foreground color and I for high-intensity background color.

Examples:

attrcolor b "R"

Change the color to bright red if bold text is to be printed.

attrcolor u "-u b"

Use blue text instead of underline.

attrcolor b ".I"

Use bright colors for bold text. Most terminal emulators do this already.

attrcolor i "+b"

Make bright colored text also bold.