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SCREEN(1)							     SCREEN(1)

NAME
       screen -	screen manager with VT100/ANSI terminal	emulation

SYNOPSIS
       screen [	-options ] [ cmd [ args	] ]
       screen -r [[pid.]tty[.host]]
       screen -r sessionowner/[[pid.]tty[.host]]

DESCRIPTION
       Screen is a full-screen window manager that multiplexes a physical ter-
       minal between several processes (typically interactive  shells).	  Each
       virtual terminal	provides the functions of a DEC	VT100 terminal and, in
       addition, several control functions from	the ISO	6429  (ECMA  48,  ANSI
       X3.64)  and ISO 2022 standards (e.g. insert/delete line and support for
       multiple	character sets).  There	is a  scrollback  history  buffer  for
       each virtual terminal and a copy-and-paste mechanism that allows	moving
       text regions between windows.

       When screen is called, it creates a single window with a	 shell	in  it
       (or  the	 specified  command) and then gets out of your way so that you
       can use the program as you normally would.  Then, at any	time, you  can
       create new (full-screen)	windows	with other programs in them (including
       more shells), kill existing windows, view a list	of windows, turn  out-
       put  logging  on	and off, copy-and-paste	text between windows, view the
       scrollback history, switch between windows in whatever manner you wish,
       etc.  All  windows  run	their  programs	completely independent of each
       other. Programs continue	to run when their window is currently not vis-
       ible and	even when the whole screen session is detached from the	user's
       terminal.  When a program terminates, screen (per  default)  kills  the
       window  that  contained	it.  If	this window was	in the foreground, the
       display switches	to the previous	 window;  if  none  are	 left,	screen
       exits.

       Everything  you type is sent to the program running in the current win-
       dow.  The only exception	to this	is the one keystroke that is  used  to
       initiate	 a  command  to	 the window manager.  By default, each command
       begins with a control-a (abbreviated C-a	from now on), and is  followed
       by one other keystroke.	The command character and all the key bindings
       can be fully customized to be anything you like,	though they are	always
       two characters in length.

       Screen does not understand the prefix "C-" to mean control.  Please use
       the caret notation ("^A"	instead	of "C-a") as  arguments	 to  e.g.  the
       escape  command	or  the	-e option.  Screen will	also print out control
       characters in caret notation.

       The standard way	to create a new	window is to type "C-a c".  This  cre-
       ates  a	new window running a shell and switches	to that	window immedi-
       ately, regardless of the	state of the process running  in  the  current
       window.	 Similarly,  you can create a new window with a	custom command
       in it by	first binding the command to a keystroke  (in  your  .screenrc
       file  or	 at  the "C-a :" command line) and then	using it just like the
       "C-a c" command.	 In addition, new windows can be created by running  a
       command like:

	      screen emacs prog.c

       from  a shell prompt within a previously	created	window.	 This will not
       run another copy	of screen, but will instead supply  the	 command  name
       and its arguments to the	window manager (specified in the $STY environ-
       ment variable) who will use it to create	the  new  window.   The	 above
       example would start the emacs editor (editing prog.c) and switch	to its
       window.

       If "/etc/utmp" is writable by screen, an	 appropriate  record  will  be
       written	to  this  file for each	window,	and removed when the window is
       terminated.  This is useful for working with "talk",  "script",	"shut-
       down",  "rsend",	 "sccs"	 and  other similar programs that use the utmp
       file to determine who you are. As long as screen	is active on your ter-
       minal,  the  terminal's	own  record is removed from the	utmp file. See
       also "C-a L".

GETTING	STARTED
       Before you begin	to use screen you'll need to make sure you  have  cor-
       rectly  selected	 your  terminal	 type, just as you would for any other
       termcap/terminfo	program.  (You can do this by using tset for example.)

       If  you're  impatient  and want to get started without doing a lot more
       reading,	you should remember this one command:  "C-a ?".	 Typing	 these
       two characters will display a list of the available screen commands and
       their bindings. Each keystroke is discussed in the section "DEFAULT KEY
       BINDINGS".  The	manual section "CUSTOMIZATION" deals with the contents
       of your .screenrc.

       If your terminal	is a "true" auto-margin	terminal (it doesn't allow the
       last position on	the screen to be updated without scrolling the screen)
       consider	using a	version	of your	terminal's termcap that	has  automatic
       margins	turned off. This will ensure an	accurate and optimal update of
       the screen in all circumstances.	Most terminals nowadays	 have  "magic"
       margins	(automatic margins plus	usable last column). This is the VT100
       style type and perfectly	suited for screen.  If all  you've  got	 is  a
       "true"  auto-margin  terminal  screen  will  be	content	to use it, but
       updating	a character put	into the last position on the screen  may  not
       be  possible  until the screen scrolls or the character is moved	into a
       safe position in	some other way.	This delay can be shortened by using a
       terminal	with insert-character capability.

COMMAND-LINE OPTIONS
       Screen has the following	command-line options:

       -a   include all	capabilities (with some	minor exceptions) in each win-
	    dow's termcap, even	if screen must redraw parts of the display  in
	    order to implement a function.

       -A   Adapt  the	sizes of all windows to	the size of the	current	termi-
	    nal.  By default, screen tries to restore  its  old	 window	 sizes
	    when  attaching  to	 resizable  terminals  (those with "WS"	in its
	    description, e.g. suncmd or	some xterm).

       -c file
	    override the default configuration file from "$HOME/.screenrc"  to
	    file.

       -d|-D [pid.tty.host]
	    does  not  start screen, but detaches the elsewhere	running	screen
	    session. It	has the	same effect as typing "C-a  d"	from  screen's
	    controlling	 terminal.  -D	is  the	equivalent to the power	detach
	    key.  If no	session	can be detached, this option  is  ignored.  In
	    combination	 with  the  -r/-R  option more powerful	effects	can be
	    achieved:

       -d -r   Reattach	a session and if necessary detach it first.

       -d -R   Reattach	a session and if necessary detach or  even  create  it
	       first.

       -d -RR  Reattach	 a  session  and if necessary detach or	create it. Use
	       the first session if more than one session is available.

       -D -r   Reattach	a session. If necessary	 detach	 and  logout  remotely
	       first.

       -D -R   Attach here and now. In detail this means: If a session is run-
	       ning, then reattach. If necessary detach	 and  logout  remotely
	       first.	If  it	was not	running	create it and notify the user.
	       This is the author's favorite.

       -D -RR  Attach here and now. Whatever that means, just do it.

	    Note: It is	always a good idea to check the	status	of  your  ses-
	    sions by means of "screen -list".

       -e xy
	    specifies the command character to be x and	the character generat-
	    ing	a literal command character to y (when typed after the command
	    character).	  The default is "C-a" and `a',	which can be specified
	    as "-e^Aa".	 When creating a screen	session, this option sets  the
	    default  command character.	In a multiuser session all users added
	    will start off with	this command character.	But when attaching  to
	    an	already	 running session, this option changes only the command
	    character of the attaching user.  This  option  is	equivalent  to
	    either the commands	"defescape" or "escape"	respectively.

       -f, -fn,	and -fa
	    turns  flow-control	 on, off, or "automatic	switching mode".  This
	    can	also be	defined	through	the "defflow" .screenrc	command.

       -h num
	    Specifies the history scrollback buffer to be num lines high.

       -i   will cause the interrupt key (usually C-c) to interrupt  the  dis-
	    play  immediately  when  flow-control  is  on.   See the "defflow"
	    .screenrc command for details.  The	use of this option is discour-
	    aged.

       -l and -ln
	    turns  login  mode	on  or off (for	/etc/utmp updating).  This can
	    also be defined through the	"deflogin" .screenrc command.

       -ls and -list
	    does not start screen, but prints a	list of	 pid.tty.host  strings
	    identifying	 your screen sessions.	Sessions marked	`detached' can
	    be resumed with "screen -r". Those marked `attached'  are  running
	    and	 have a	controlling terminal. If the session runs in multiuser
	    mode, it is	 marked	 `multi'.  Sessions  marked  as	 `unreachable'
	    either  live  on  a	 different host	or are `dead'.	An unreachable
	    session is considered dead,	when its name matches either the  name
	    of the local host, or the specified	parameter, if any.  See	the -r
	    flag for a description how to construct matches.  Sessions	marked
	    as `dead' should be	thoroughly checked and removed.	 Ask your sys-
	    tem	administrator if you are not sure. Remove  sessions  with  the
	    -wipe option.

       -L   tells  screen to turn on automatic output logging for the windows.

       -m   causes screen  to  ignore  the  $STY  environment  variable.  With
	    "screen  -m"  creation  of	a  new session is enforced, regardless
	    whether screen is called from within  another  screen  session  or
	    not.  This	flag has a special meaning in connection with the `-d'
	    option:

       -d -m   Start screen in "detached" mode.	This creates a new session but
	       doesn't	attach	to  it.	 This  is  useful  for	system startup
	       scripts.

       -D -m   This also starts	screen in "detached" mode, but doesn't fork  a
	       new process. The	command	exits if the session terminates.

       -O   selects  a	more optimal output mode for your terminal rather than
	    true VT100 emulation (only affects auto-margin  terminals  without
	    `LP').   This can also be set in your .screenrc by specifying `OP'
	    in a "termcap" command.

       -p number_or_name
	    Preselect a	window.	This is	usefull	when you want to reattach to a
	    specific  windor or	you want to send a command via the "-X"	option
	    to a specific window. As with screen's select commant, "-" selects
	    the	 blank	window.	 As a special case for reattach, "=" brings up
	    the	windowlist on the blank	window.

       -q   Suppress printing of error messages. In combination	with "-ls" the
	    exit  value	 is  as	 follows: 9 indicates a	directory without ses-
	    sions. 10 indicates	a directory with running  but  not  attachable
	    sessions.  11 (or more) indicates 1	(or more) usable sessions.  In
	    combination	with "-r" the exit value is as follows:	 10  indicates
	    that  there	 is  no	session	to resume. 12 (or more)	indicates that
	    there are 2	(or more) sessions to resume and  you  should  specify
	    which one to choose.  In all other cases "-q" has no effect.

       -r [pid.tty.host]
       -r sessionowner/[pid.tty.host]
	    resumes  a detached	screen session.	 No other options (except com-
	    binations with -d/-D) may be specified, though an optional	prefix
	    of	[pid.]tty.host	may  be	needed to distinguish between multiple
	    detached screen sessions.  The second form is used to  connect  to
	    another  user's  screen session which runs in multiuser mode. This
	    indicates that screen should look for sessions in  another	user's
	    directory. This requires setuid-root.

       -R   attempts to	resume the first detached screen session it finds.  If
	    successful,	all other command-line options	are  ignored.	If  no
	    detached  session exists, starts a new session using the specified
	    options, just as if	-R had not been	specified. The option  is  set
	    by default if screen is run	as a login-shell (actually screen uses
	    "-xRR" in that case).  For combinations with the -d/-D option  see
	    there.

       -s   sets  the  default	shell to the program specified,	instead	of the
	    value in the environment variable  $SHELL  (or  "/bin/sh"  if  not
	    defined).	This can also be defined through the "shell" .screenrc
	    command.

       -S sessionname
	    When creating a new	session, this option can be used to specify  a
	    meaningful	name for the session. This name	identifies the session
	    for	"screen	-list" and "screen -r"	actions.  It  substitutes  the
	    default [tty.host] suffix.

       -t name
	    sets  the  title  (a.k.a.) for the default shell or	specified pro-
	    gram.  See also the	"shelltitle" .screenrc command.

       -U   Run	screen in UTF-8	mode. This option tells	screen that your  ter-
	    minal sends	and understands	UTF-8 encoded characters. It also sets
	    the	default	encoding for new windows to `utf8'.

       -v   Print version number.

       -wipe [match]
	    does the same as "screen  -ls",  but  removes  destroyed  sessions
	    instead of marking them as `dead'.	An unreachable session is con-
	    sidered dead, when its name	matches	either the name	of  the	 local
	    host,  or the explicitly given parameter, if any.  See the -r flag
	    for	a description how to construct matches.

       -x   Attach to a	not detached screen session. (Multi display mode).

       -X   Send the specified command to a running screen  session.  You  can
	    use	 the  -d or -r option to tell screen to	look only for attached
	    or detached	screen sessions. Note that this	command	 doesn't  work
	    if the session is password protected.

DEFAULT	KEY BINDINGS
       As  mentioned,  each screen 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 counter-
       parts (with the exception of "C-a a"; see below), thus, "C-a c" as well
       as  "C-a	 C-c"  can be used to create a window. See section "CUSTOMIZA-
       TION" for a description of the command.

       The following table shows the default key bindings:

       C-a '	   (select)	 Prompt	for a window name or number to	switch
				 to.

       C-a "	   (windowlist -b)
				 Present  a list of all	windows	for selection.

       C-a 0	   (select 0)
	...	      ...
       C-a 9	   (select 9)
       C-a -	   (select -)	 Switch	to window number 0  -  9,  or  to  the
				 blank window.

       C-a tab	   (focus)	 Switch	the input focus	to the next region.

       C-a C-a	   (other)	 Toggle	 to  the  window displayed previously.
				 Note that this	binding	defaults to  the  com-
				 mand  character  typed	twice, unless overrid-
				 den.  For instance, if	 you  use  the	option
				 "-e]x", this command becomes "]]".

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

       C-a A	   (title)	 Allow the user	to enter a name	for  the  cur-
				 rent window.

       C-a b
       C-a C-b	   (break)	 Send a	break to window.

       C-a B	   (pow_break)	 Reopen	the terminal line and send a break.

       C-a c
       C-a C-c	   (screen)	 Create	 a  new	window with a shell and	switch
				 to that window.

       C-a C	   (clear)	 Clear the screen.

       C-a d
       C-a C-d	   (detach)	 Detach	screen from this terminal.

       C-a D D	   (pow_detach)	 Detach	and logout.

       C-a f
       C-a C-f	   (flow)	 Toggle	flow on, off or	auto.

       C-a F	   (fit)	 Resize	the window to the current region size.

       C-a C-g	   (vbell)	 Toggles screen's visual bell mode.

       C-a h	   (hardcopy)	 Write a hardcopy of the current window	to the
				 file "hardcopy.n".

       C-a H	   (log)	 Begins/ends logging of	the current window  to
				 the file "screenlog.n".

       C-a i
       C-a C-i	   (info)	 Show info about this window.

       C-a k
       C-a C-k	   (kill)	 Destroy current window.

       C-a l
       C-a C-l	   (redisplay)	 Fully refresh current window.

       C-a L	   (login)	 Toggle	 this  windows	login  slot. Available
				 only if screen	is configured  to  update  the
				 utmp database.

       C-a m
       C-a C-m	   (lastmsg)	 Repeat	the last message displayed in the mes-
				 sage line.

       C-a M	   (monitor)	 Toggles monitoring of the current window.

       C-a space
       C-a n
       C-a C-n	   (next)	 Switch	to the next window.

       C-a N	   (number)	 Show the number (and title)  of  the  current
				 window.

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

       C-a q
       C-a C-q	   (xon)	 Send a	control-q to the current window.

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

       C-a r
       C-a C-r	   (wrap)	 Toggle	the current window's line-wrap setting
				 (turn	the current window's automatic margins
				 on and	off).

       C-a s
       C-a C-s	   (xoff)	 Send a	control-s to the current window.

       C-a S	   (split)	 Split the current region into two new ones.

       C-a t
       C-a C-t	   (time)	 Show system information.

       C-a v	   (version)	 Display the version and compilation date.

       C-a C-v	   (digraph)	 Enter digraph.

       C-a w
       C-a C-w	   (windows)	 Show a	list of	window.

       C-a W	   (width)	 Toggle	80/132 columns.

       C-a x
       C-a C-x	   (lockscreen)	 Lock this terminal.

       C-a X	   (remove)	 Kill the current region.

       C-a z
       C-a C-z	   (suspend)	 Suspend screen.   Your	 system	 must  support
				 BSD-style job-control.

       C-a Z	   (reset)	 Reset	the virtual terminal to	its "power-on"
				 values.

       C-a .	   (dumptermcap) Write out a ".termcap"	file.

       C-a ?	   (help)	 Show key bindings.

       C-a C-\	   (quit)	 Kill all windows and terminate	screen.

       C-a :	   (colon)	 Enter command line mode.

       C-a [
       C-a C-[
       C-a esc	   (copy)	 Enter copy/scrollback mode.

       C-a ]	   (paste .)	 Write the contents of the paste buffer	to the
				 stdin queue of	the current window.

       C-a {
       C-a }	   (history)	 Copy and paste	a previous (command) line.

       C-a >	   (writebuf)	 Write paste buffer to a file.

       C-a <	   (readbuf)	 Reads the screen-exchange file	into the paste
				 buffer.

       C-a =	   (removebuf)	 Removes the file used by C-a <	and C-a	>.

       C-a ,	   (license)	 Shows where screen comes from,	where it  went
				 to and	why you	can use	it.

       C-a _	   (silence)	 Start/stop  monitoring	the current window for
				 inactivity.

       C-a *	   (displays)	 Show a	listing	of all currently attached dis-
				 plays.

CUSTOMIZATION
       The  "socket  directory"	 defaults either to $HOME/.screen or simply to
       /tmp/screens or preferably to  /usr/local/screens  chosen  at  compile-
       time. If	screen is installed setuid-root, then the administrator	should
       compile screen with an adequate (not NFS	mounted) socket	directory.  If
       screen  is  not	running	setuid-root, the user can specify any mode 700
       directory in the	environment variable $SCREENDIR.

       When screen is invoked, it executes initialization  commands  from  the
       files  "/usr/local/etc/screenrc"	 and  ".screenrc"  in  the user's home
       directory. These	are the	"programmer's defaults"	that 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
       in $SCREENRC, then $HOME/.screenrc.  The	command	line option  -c	 takes
       precedence over the above user screenrc files.

       Commands	 in  these  files  are	used to	set options, bind functions to
       keys, and to automatically establish one	or more	windows	at the	begin-
       ning  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.   Unintel-
       ligible	lines are warned about and ignored.  Commands may contain ref-
       erences 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 shall be performed. A string in single-quotes is
       also protected from variable substitution.

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

       Customization can also be done 'on-line'. To  enter  the	 command  mode
       type  `C-a  :'.	Note  that commands starting with "def"	change default
       values, while others change current settings.

       The following commands are available:

       acladd usernames	[crypted-pw]
       addacl usernames

       Enable users to fully access this screen	session. Usernames can be  one
       user or a comma separated list of users.	This command enables to	attach
       to the screen session and performs the equivalent of `aclchg  usernames
       +rwx  "#?"'.   executed.	 To add	a user with restricted access, use the
       `aclchg'	command	below.	If an optional second parameter	 is  supplied,
       it  should  be  a crypted password for the named	user(s). `Addacl' is a
       synonym to `acladd'.  Multi user	mode only.

       aclchg usernames	permbits list
       chacl usernames permbits	list

       Change permissions for a	comma separated	list of	users. Permission bits
       are  represented	 as `r', `w' and `x'. Prefixing	`+' grants the permis-
       sion, `-' removes it. The third parameter is a comma separated list  of
       commands	and/or windows (specified either by number or title). The spe-
       cial list `#' refers to all windows, `?'	to all commands. if  usernames
       consists	 of a single `*', all known users are affected.	 A command can
       be executed when	the user has the `x' bit for it.  The  user  can  type
       input to	a window when he has its `w' bit set and no other user obtains
       a writelock for this window.  Other bits	 are  currently	 ignored.   To
       withdraw	 the writelock from another user in window 2: `aclchg username
       -w+w 2'.	 To allow read-only access to the session: `aclchg username -w
       "#"'.  As soon as a user's name is known	to screen he can attach	to the
       session and (per	default) has full permissions for all command and win-
       dows. Execution permission for the acl commands,	`at' and others	should
       also be removed or the user may be able	to  regain  write  permission.
       Rights  of  the special username	nobody cannot be changed (see the "su"
       command).  `Chacl' is a synonym to `aclchg'.  Multi user	mode only.

       acldel username

       Remove a	user from screen's access control list.	If currently attached,
       all the user's displays are detached from the session. He cannot	attach
       again.  Multi user mode only.

       aclgrp username [groupname]

       Creates groups of users that share common access	rights.	 The  name  of
       the group is the	username of the	group leader. Each member of the group
       inherits	the permissions	that are granted to  the  group	 leader.  That
       means,  if  a user fails	an access check, another check is made for the
       group leader.  A	user is	removed	from  all  groups  the	special	 value
       "none"  is  used	for groupname.	If the second parameter	is omitted all
       groups the user is in are listed.

       aclumask	[[users]+bits |[users]-bits .... ]
       umask [[users]+bits |[users]-bits .... ]

       This specifies the access other users have to windows that will be cre-
       ated  by	 the  caller  of the command.  Users may be no,	one or a comma
       separated list of known usernames. If no	users are specified, a list of
       all  currently  known  users  is	 assumed.   Bits is any	combination of
       access control bits allowed defined with	the "aclchg" command. The spe-
       cial  username  "?" predefines the access that not yet known users will
       be granted to any window	initially.  The	special	username  "??"	prede-
       fines  the  access that not yet known users are granted to any command.
       Rights of the special username nobody cannot be changed (see  the  "su"
       command).  `Umask' is a synonym to `aclumask'.

       activity	message

       When  any  activity  occurs  in a background window that	is being moni-
       tored, screen displays a	notification in	the message line.  The notifi-
       cation  message	can  be	re-defined by means of the "activity" command.
       Each occurrence of `%' in message is replaced by	the number of the win-
       dow  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).

       allpartial on|off

       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.

       altscreen on|off

       If  set	to on, "alternate screen" support is enabled in	virtual	termi-
       nals, just like in xterm.  Initial setting is `off'.

       at [identifier][#|*|%] command [args ...	]

       Execute a command at other displays  or	windows	 as  if	 it  had  been
       entered there.  "At" changes the	context	(the `current window' or `cur-
       rent 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 dis-
       play 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.
       Permission is checked for initiator of the "at" command,	 not  for  the
       owners  of  the affected	display(s).  Note that the '#' character works
       as a comment introducer when it is preceded by whitespace. This can  be
       escaped by prefixing 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 win-
       dows (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. "process") require  that  a
       display	is associated with the target windows.	These commands may not
       work correctly under "at" looping over windows.

       attrcolor attrib	[attribute/color-modifier]

       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 "STRING ESCAPES"	chapter	for the	syntax
       of the modifier.	Screen understands two pseudo-attributes,  "i"	stands
       for  high-intensity  foreground	color and "I" for high-intensity back-
       ground 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.

       autodetach on|off

       Sets  whether screen will automatically detach upon hangup, which saves
       all your	running	programs until they are	resumed	with a screen -r  com-
       mand.   When  turned off, a hangup signal will terminate	screen and all
       the processes it	contains. Autodetach is	on by default.

       autonuke	on|off

       Sets whether a clear screen sequence should nuke	all  the  output  that
       has not been written to the terminal. See also "obuflimit".

       backtick	id lifespan autorefresh	cmd args...
       backtick	id

       Program	the  backtick command with the numerical id id.	 The output of
       such a command is used for substitution of the "%`" string escape.  The
       specified  lifespan  is	the number of seconds the output is considered
       valid. After this time, the command is run  again  if  a	 corresponding
       string  escape  is  encountered.	 The autorefresh parameter triggers an
       automatic refresh for caption and hardstatus strings after  the	speci-
       fied  number  of	seconds. Only the last line of output is used for sub-
       stitution.
       If both the lifespan and	the autorefresh	parameters are zero, the back-
       tick  program is	expected to stay in the	background and generate	output
       once in a while.	 In this case, the command is executed right away  and
       screen  stores  the  last  line	of  output. If a new line gets printed
       screen will automatically refresh the hardstatus	or the captions.
       The second form of the command deletes the backtick  command  with  the
       numerical id id.

       bce [on|off]

       Change background-color-erase setting. If "bce" is set to on, all char-
       acters cleared by an erase/insert/scroll/clear operation	will  be  dis-
       played  in  the	current	 background color. Otherwise the default back-
       ground color is used.

       bell_msg	[message]

       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 term-
       cap (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	parameter, the current
       message is shown.

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

       Bind  a command to a key.  By default, most of the commands provided by
       screen are bound	to one or more keys as indicated in the	 "DEFAULT  KEY
       BINDINGS"  section, e.g.	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.  The key argument is either	a sin-
       gle 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	listed in this
       section.

       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.

       Some examples:

		   bind	' ' windows
		   bind	^k
		   bind	k
		   bind	K kill
		   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	avail-
       able  as	 "C-a  space").	 The  next three lines remove the default kill
       binding from "C-a C-k" and "C-a k".  "C-a K" is then bound to the  kill
       command.	 Then  it  binds  "C-f"	to the command "create a window	with a
       TELNET connection to foobar", and bind "escape"	to  the	 command  that
       creates an non-login window with	a.k.a. "root" in slot #9, with a supe-
       ruser 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.

       bindkey [-d] [-m] [-a] [[-k|-t] string [cmd args]]

       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 con-
       tain  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  section	"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 key-
       board capability	name (selectable with the -k option).
       Some keys on a VT100 terminal can send a	different string  if  applica-
       tion  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.
       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	 "^T" an escape	character for key-bindings. If
       you did the above "stuff	barfoo"	binding, you can enter the word	 "foo"
       by  typing  "^Tfoo". If you want	to insert a "^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	^A).

       break [duration]

       Send a break signal for duration*0.25 seconds to	this window.  For non-
       Posix  systems  the  time  interval  may	be rounded up to full seconds.
       Most useful if a	character device is attached to	the window rather than
       a shell process (See also chapter "WINDOW TYPES"). The maximum duration
       of a break signal is limited to 15 seconds.

       blanker

       Activate	the screen blanker. First the screen is	cleared. If no blanker
       program is defined, the cursor is turned	off, otherwise,	the program is
       started and it's	output is written to the screen.  The  screen  blanker
       is killed with the first	keypress, the read key is discarded.
       This command is normally	used together with the "idle" command.

       blankerprg [program args]

       Defines a blanker program. Disables the blanker program if no arguments
       are given.

       breaktype [tcsendbreak|TIOCSBRK |TCSBRK]

       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 method for	the current window.

       bufferfile [exchange-file]

       Change the filename used	for reading and	writing	with the paste buffer.
       If  the	optional  argument to the "bufferfile" command is omitted, the
       default setting ("/tmp/screen-exchange")	is reactivated.	 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

       c1 [on|off]

       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.

       caption always|splitonly	[string]
       caption string [string]

       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
       escapes from the	"STRING	ESCAPES" chapter. Screen  uses	a  default  of
       `%3n %t'.

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

       charset set

       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 indi-
       cate 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.

       chdir [directory]

       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.

       clear

       Clears the current window and saves its image to	the scrollback buffer.

       colon [prefix]

       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!	 Usually  com-
       mands affect the	current	window rather than default settings for	future
       windows.	Change defaults	with commands starting with 'def...'.

       If you consider this as the `Ex command mode' of	screen,	you may	regard
       "C-a esc" (copy mode) as	its `Vi	command	mode'.

       command [-c class]

       This  command has the same effect as typing the screen escape character
       (^A). It	is probably only useful	for key	bindings.  If the "-c"	option
       is  given,  select  the	specified  command class.  See also "bind" and
       "bindkey".

       compacthist [on|off]

       This tells  screen  whether  to	suppress  trailing  blank  lines  when
       scrolling up text into the history buffer.

       console [on|off]

       Grabs  or un-grabs the machines console output to a window.  Note: Only
       the owner of /dev/console can grab the console output.  This command is
       only available if the machine supports the ioctl	TIOCCONS.

       copy

       Enter  copy/scrollback mode. This allows	you to copy text from the cur-
       rent window and its history into	the paste buffer. In this mode	a  vi-
       like `full screen editor' is active:
       Movement	keys:
	 h, j, k, l move the cursor line by line or column by column.
	 0,  ^	and  $	move to	the leftmost column, to	the first or last non-
	   whitespace character	on the line.
	 H, M and L move the cursor to the leftmost column of the top,	center
	   or bottom line of the window.
	 + and - positions one line up and down.
	 G moves to the	specified absolute line	(default: end of buffer).
	 | moves to the	specified absolute column.
	 w, b, e move the cursor word by word.
	 B, E move the cursor WORD by WORD (as in vi).
	 C-u  and  C-d	scroll	the display up/down by the specified amount of
	   lines while preserving the cursor position. (Default: half  screen-
	   full).
	 C-b and C-f scroll the	display	up/down	a full screen.
	 g moves to the	beginning of the buffer.
	 % jumps to the	specified percentage of	the buffer.

       Note:
	   Emacs style movement	keys can be customized by a .screenrc command.
	   (E.g. markkeys "h=^B:l=^F:$=^E") There is no	simple	method	for  a
	   full	emacs-style keymap, as this involves multi-character codes.

       Marking:
	   The	copy range is specified	by setting two marks. The text between
	   these marks will be highlighted. Press
	 space to set the first	or second mark respectively.
	 Y and y used to mark one whole	line or	to mark	from start of line.
	 W marks exactly one word.
       Repeat count:
	   Any of these	commands can be	prefixed with a	repeat count number by
	   pressing digits
	 0..9 which is taken as	a repeat count.
	   Example:  "C-a  C-[	H  10 j	5 Y" will copy lines 11	to 15 into the
	   paste buffer.
       Searching:
	 / Vi-like search forward.
	 ? Vi-like search backward.
	 C-a s Emacs style incremental search forward.
	 C-r Emacs style reverse i-search.
       Specials:
	   There are however some keys that act	differently than  in  vi.   Vi
	   does	 not  allow one	to yank	rectangular blocks of text, but	screen
	   does. Press
	 c or C	to set the left	or right margin	 respectively.	If  no	repeat
	   count is given, both	default	to the current cursor position.
	   Example: Try	this on	a rather full text screen: "C-a	[ M 20 l SPACE
	   c 10	l 5 j C	SPACE".

	   This	moves one to the middle	line of	the screen, moves in  20  col-
	   umns	 left,	marks the beginning of the paste buffer, sets the left
	   column, moves 5 columns down, sets the right	column,	and then marks
	   the end of the paste	buffer.	Now try:
	   "C-a	[ M 20 l SPACE 10 l 5 j	SPACE"

	   and notice the difference in	the amount of text copied.
	 J  joins lines. It toggles between 4 modes: lines separated by	a new-
	   line	character (012), lines glued seamless, lines  separated	 by  a
	   single  whitespace  and  comma  separated  lines. Note that you can
	   prepend the newline character with a	carriage return	character,  by
	   issuing a "crlf on".
	 v  is	for all	the vi users with ":set	numbers" - it toggles the left
	   margin between column 9 and 1. Press
	 a before the final space key to toggle	in append mode.	Thus the  con-
	   tents  of the paste buffer will not be overwritten, but is appended
	   to.
	 A toggles in append mode and sets a (second) mark.
	 > sets	the (second) mark and writes the contents of the paste	buffer
	   to the screen-exchange file (/tmp/screen-exchange per default) once
	   copy-mode is	finished.
	   This	example	demonstrates how to dump the whole  scrollback	buffer
	   to that file: "C-A [	g SPACE	G $ >".
	 C-g gives information about the current line and column.
	 x  exchanges  the first mark and the current cursor position. You can
	   use this to adjust an already placed	mark.
	 @ does	nothing. Does not even exit copy mode.
	 All keys not described	here exit copy mode.

       copy_reg	[key]

       No longer exists, use "readreg" instead.

       crlf [on|off]

       This affects the	copying	of text	regions	with the `C-a ['  command.  If
       it  is  set  to	`on',  lines  will  be	separated by the two character
       sequence	`CR' - `LF'.  Otherwise	(default) only `LF' is used.  When  no
       parameter is given, the state is	toggled.

       debug on|off

       Turns  runtime  debugging  on  or off. If screen	has been compiled with
       option -DDEBUG debugging	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.

       defc1 on|off

       Same  as	the c1 command except that the default setting for new windows
       is changed. Initial setting is `on'.

       defautonuke on|off

       Same as the autonuke command except that	the default  setting  for  new
       displays	 is  changed. Initial setting is `off'.	 Note that you can use
       the special `AN'	terminal capability if you want	to have	 a  dependency
       on the terminal type.

       defbce on|off

       Same as the bce command except that the default setting for new windows
       is changed. Initial setting is `off'.

       defbreaktype [tcsendbreak|TIOCSBRK |TCSBRK]

       Choose one of the available methods of generating a  break  signal  for
       terminal	 devices.  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 dependant,	this also dif-
       fers between serial board  drivers.   Calling  "defbreaktype"  with  no
       parameter displays the current setting.

       defcharset [set]

       Like  the  charset command except that the default setting for new win-
       dows is changed.	Shows current default if called	without	argument.

       defescape xy

       Set the default command characters. This	is equivalent to the  "escape"
       except  that  it	is useful multiuser sessions only. In a	multiuser ses-
       sion "escape" changes the command character of the calling user,	 where
       "defescape"  changes the	default	command	characters for users that will
       be added	later.

       defflow on|off|auto [interrupt]

       Same as the flow	command	except that the	default	setting	for  new  win-
       dows  is	 changed. Initial setting is `auto'.  Specifying "defflow auto
       interrupt" is the same as the command-line options -fa and -i.

       defgr on|off

       Same as the gr command except that the default setting for new  windows
       is changed. Initial setting is `off'.

       defhstatus [status]

       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  charac-
       ter is '^E' (octal 005) instead of '%'.	This was done to make a	misin-
       terpretation 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.

       defencoding enc

       Same as the encoding command except that	the default  setting  for  new
       windows is changed. Initial setting is the encoding taken from the ter-
       minal.

       deflog on|off

       Same as the log command except that the default setting for new windows
       is changed. Initial setting is `off'.

       deflogin	on|off

       Same  as	the login command except that the default setting for new win-
       dows is changed.	This is	initialized with `on' as distributed (see con-
       fig.h.in).

       defmode mode

       The mode	of each	newly allocated	pseudo-tty is set to mode.  Mode is an
       octal number.  When no "defmode"	command	is given, mode 0622 is used.

       defmonitor on|off

       Same as the monitor command except that the  default  setting  for  new
       windows is changed. Initial setting is `off'.

       defnonblock on|off|numsecs

       Same  as	 the nonblock command except that the default setting for dis-
       plays is	changed. Initial setting is `off'.

       defobuflimit limit

       Same as the obuflimit command except that the default setting  for  new
       displays	 is  changed. Initial setting is 256 bytes.  Note that you can
       use the special 'OL' terminal capability	if you want to have  a	depen-
       dency on	the terminal type.

       defscrollback num

       Same  as	the scrollback command except that the default setting for new
       windows is changed. Initial setting is 100.

       defshell	command

       Synonym to the shell command. See there.

       defsilence on|off

       Same as the silence command except that the  default  setting  for  new
       windows is changed. Initial setting is `off'.

       defslowpaste msec"

       Same  as	 the slowpaste command except that the default setting for new
       windows is changed. Initial setting is 0	milliseconds, meaning `off'.

       defutf8 on|off

       Same as the utf8	command	except that the	default	setting	for  new  win-
       dows  is	 changed.  Initial  setting is `on' if screen was started with
       "-U", otherwise `off'.

       defwrap on|off

       Same as the wrap	command	except that the	default	setting	for  new  win-
       dows  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".

       defwritelock on|off|auto

       Same as the writelock command except that the default setting  for  new
       windows is changed. Initially writelocks	will off.

       defzombie [keys]

       Synonym	to the zombie command. Both currently change the default.  See
       there.

       detach [-h]

       Detach the screen session (disconnect it	from the terminal and  put  it
       into  the background).  This returns you	to the shell where you invoked
       screen.	A detached screen can be resumed by invoking screen  with  the
       -r  option  (see	 also  section	"COMMAND-LINE OPTIONS"). The -h	option
       tells screen to	immediately  close  the	 connection  to	 the  terminal
       ("hangup").

       dinfo

       Show what screen	thinks about your terminal. Useful if you want to know
       why features like color or the alternate	charset	don't work.

       displays

       Shows a tabular listing of  all	currently  connected  user  front-ends
       (displays).  This is most useful	for multiuser sessions.

       digraph [preset]

       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 exam-
       ple the command "bindkey	^K digraph '"'"	enables	the user  to  generate
       an a-umlaut by typing CTRL-K a.

       dumptermcap

       Write the termcap entry for the virtual terminal	optimized for the cur-
       rently  active  window  to  the	 file	".termcap"   in	  the	user's
       "$HOME/.screen"	directory  (or wherever	screen stores its sockets. See
       the "FILES" section below).  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  con-
       verter like captoinfo and then compile the entry	with tic.

       echo [-n] message

       The  echo  command may be used to annoy screen users with a 'message of
       the day'. Typically installed in	 a  global  /local/etc/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.

       encoding	enc [enc]

       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	termi-
       nal  encoding  depending	on the terminal	type by	using the "KJ" termcap
       entry.

       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 win-
       dow.

       escape xy

       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  fol-
       lowed  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".

       eval command1 [command2 ...]

       Parses and executes each	argument as separate command.

       exec [[fdpat] newcommand	[args ...]]

       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	in the
       window (let us call it "application-process") and screen	 itself	 (win-
       dow)  is	 controlled by the filedescriptor 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'  out-
       put  (fdpats  first  character  is  `!' or `:') or a pipe symbol	(|) is
       added (as a fourth character) to	the end	of fdpat.
       Invoking	`exec' without arguments shows name and	arguments of the  cur-
       rently  running	subprocess  in this window. Only one subprocess	a time
       can be running in each window.
       When a subprocess is running the	`kill' command will affect it  instead
       of the windows process.
       Refer  to  the postscript file `doc/fdpat.ps' for a confusing illustra-
       tion 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 the 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.

       Abbreviations:
       Whitespace between the word `exec' and fdpat and	 the  command  can  be
       omitted.	Trailing dots and a fdpat consisting only of dots can be omit-
       ted. A simple `|' is synonymous for the pattern `!..|'; the  word  exec
       can be omitted here and can always be replaced by `!'.

       Examples:

	      exec ... /bin/sh
	      exec /bin/sh
	      !/bin/sh

       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.

	      exec !.. stty 19200
	      exec ! stty 19200
	      !!stty 19200

       Set  the	 speed	of  the	window's tty. If your stty command operates on
       stdout, then add	another	`!'.

	      exec !..|	less
	      |less

       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.

       fit

       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.

       flow [on|off|auto]

       Sets the	flow-control mode for  this  window.   Without	parameters  it
       cycles  the  current  window's flow-control setting from	"automatic" to
       "on" to "off".  See the discussion on "FLOW-CONTROL" later on  in  this
       document	 for  full details and note, that this is subject to change in
       future releases.	 Default is set	by `defflow'.

       focus [up|down|top|bottom]

       Move the	input focus to the next	region.	This is	done in	a  cyclic  way
       so  that	the top	region is selected after the bottom one. If no subcom-
       mand is given it	defaults to `down'. `up' cycles	in the opposite	order,
       `top' and `bottom' go to	the top	and bottom region respectively.	Useful
       bindings	are (j and k as	in vi)
	   bind	j focus	down
	   bind	k focus	up
	   bind	t focus	top
	   bind	b focus	bottom

       gr [on|off]

       Turn GR charset switching on/off. Whenever screen sees an input charac-
       ter with	the 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.

       hardcopy	[-h] [file]

       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. See below.  If the option -h is specified, dump
       also the	contents of the	scrollback buffer.

       hardcopy_append on|off

       If set to "on", screen will append to the "hardcopy.n" files created by
       the  command  "C-a h", otherwise	these files are	overwritten each time.
       Default is `off'.

       hardcopydir directory

       Defines a directory where hardcopy files	 will  be  placed.  If	unset,
       hardcopys are dumped in screen's	current	working	directory.

       hardstatus [on|off]
       hardstatus [always]lastline|message|ignore [string]
       hardstatus string [string]

       This  command  configures the use and emulation of the terminal's hard-
       status line. The	first form toggles whether screen will use  the	 hard-
       ware  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 "lastline" is used, screen will
       reserve the 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 sup-
       ports a hardstatus.

       The third form specifies	the contents of	the hardstatus line.  '%h'  is
       used  as	default	string,	i.e. the stored	hardstatus of the current win-
       dow (settable via "ESC]0;<string>^G"  or	 "ESC_<string>ESC\")  is  dis-
       played.	 You  can  customize this to any string	you like including the
       escapes from the	"STRING	ESCAPES" chapter. If you leave out  the	 argu-
       ment string, the	current	string is displayed.

       You  can	mix the	second and third form by providing the string as addi-
       tional argument.

       height [-w|-d] [lines [cols]]

       Set the display height to a specified number of lines. When no argument
       is given	it toggles between 24 and 42 lines display. You	can also spec-
       ify a width 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.

       help [-c	class]

       Not really a online help, but displays a	help screen  showing  you  all
       the  key	bindings.  The first pages list	all the	internal commands fol-
       lowed by	their current 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 also "DEFAULT KEY BINDINGS"  section.

       history

       Usually	users  work  with  a shell that	allows easy access to previous
       commands.  For example csh has the command "!!" to repeat the last com-
       mand executed.  Screen allows you to have a primitive way of re-calling
       "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).

       hstatus status

       Change the window's hardstatus line to the string status.

       idle [timeout [cmd args]]

       Sets  a command that is run after the specified number of seconds inac-
       tivity is reached. This command will normally be	the "blanker"  command
       to  create  a  screen blanker, but it can be any	screen command.	 If no
       command is specified, only the timeout is set. A	timeout	 of  zero  (ot
       the  special  timeout  off)  disables  the  timer.  If no arguments are
       given, the current settings are displayed.

       ignorecase [on|off]

       Tell screen to ignore the case of characters in	searches.  Default  is
       `off'.

       info

       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	also section FLOW CON-
       TROL):

	 +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' or `nored'
       are displayed when the window is	in insert mode,	origin mode,  applica-
       tion-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 is	shown. 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 also chapter "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 the "time" command.

       ins_reg [key]

       No longer exists, use "paste" instead.

       kill

       Kill current window.
       If there	is an `exec' command running then it is	killed.	Otherwise  the
       process	(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.
       Note: Emacs users should	keep this command  in  mind,  when  killing  a
       line.   It  is recommended not to use "C-a" as the screen escape	key or
       to rebind kill to "C-a K".

       lastmsg

       Redisplay the last contents of  the  message/status  line.   Useful  if
       you're  typing  when  a message appears,	because	 the message goes away
       when you	press a	key (unless your terminal has a	hardware status	line).
       Refer to	the commands "msgwait" and "msgminwait"	for fine tuning.

       license

       Display	the  disclaimer	 page. This is done whenever screen is started
       without	options,  which	 should	 be  often  enough.   See   also   the
       "startup_message" command.

       lockscreen

       Lock  this  display.   Call  a  screenlock  program  (/local/bin/lck or
       /usr/bin/lock or	a builtin if no	other is available). Screen  does  not
       accept  any  command keys until this program terminates.	Meanwhile pro-
       cesses 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 you 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'.

       log [on|off]

       Start/stop writing output of the	current	window to a 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 state of	logging	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'.

       logfile filename
       logfile flush secs

       Defines	the name the logfiles 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.

       login [on|off]

       Adds or removes the entry in the	utmp database  file  for  the  current
       window.	This controls if the window is `logged in'.  When no parameter
       is given, the login state of the	window is  toggled.   Additionally  to
       that  toggle,  it  is convenient	having a `log in' and a	`log out' key.
       E.g. `bind I login on' and `bind	O login	off' will map these keys to be
       C-a  I  and C-a O.  The default setting (in config.h.in)	should be "on"
       for a screen that runs under suid-root.	Use the	"deflogin" command  to
       change  the default login state for new windows.	Both commands are only
       present when screen has been compiled with utmp support.

       logtstamp [on|off]
       logtstamp after [secs]
       logtstamp string	[string]

       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  con-
       tinues  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).

       mapdefault

       Tell  screen  that the next input character should only be looked up in
       the default bindkey table. See also "bindkey".

       mapnotnext

       Like mapdefault,	but don't even look in the default bindkey table.

       maptimeout [timo]

       Set the inter-character timer for input sequence	detection to a timeout
       of  timo	ms. The	default	timeout	is 300ms. Maptimeout with no arguments
       shows the current setting.  See also "bindkey".

       markkeys	string

       This is a method	of changing the	keymap	used  for  copy/history	 mode.
       The  string  is made up of oldchar=newchar pairs	which are separated by
       `:'. Example: The string	"B=^B:F=^F" will change	the keys `C-b' and `C-
       f' to the vi style binding (scroll up/down fill page).  This happens to
       be the  default	binding	 for  `B'  and	`F'.   The  command  "markkeys
       h=^B:l=^F:$=^E" would set the mode for an emacs-style binding.  If your
       terminal	sends characters, that cause you to abort copy mode, then this
       command	may help by binding these characters to	do nothing.  The no-op
       character is `@'	and is used like this: "markkeys @=L=H"	if you do  not
       want to use the `H' or `L' commands any longer.	As shown in this exam-
       ple, multiple keys can be assigned to one function in a	single	state-
       ment.

       maxwin num

       Set  the	 maximum  window  number  screen  will	create.	Doesn't	affect
       already existing	windows. The number may	only be	decreased.

       meta

       Insert the command  character  (C-a)  in	 the  current  window's	 input
       stream.

       monitor [on|off]

       Toggles	activity  monitoring of	windows.  When monitoring is turned on
       and an affected window  is  switched  into  the	background,  you  will
       receive	the  activity  notification  message in	the status line	at the
       first sign of output and	the window will	also be	marked with an `@'  in
       the  window-status  display.   Monitoring is initially off for all win-
       dows.

       msgminwait sec

       Defines the time	screen delays a	new message when one message  is  cur-
       rently displayed.  The default is 1 second.

       msgwait sec

       Defines	the  time a message is displayed if screen is not disturbed by
       other activity. The default is 5	seconds.

       multiuser on|off

       Switch between singleuser and multiuser mode. Standard screen operation
       is  singleuser.	In  multiuser  mode  the  commands `acladd', `aclchg',
       `aclgrp'	and `acldel' can be used to enable (and	disable)  other	 users
       accessing this screen session.

       nethack on|off

       Changes the kind	of error messages used by screen.  When	you are	famil-
       iar 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. The default setting is then determined by the presence of
       the environment variable	$NETHACKOPTIONS.

       next

       Switch to the next window.  This	command	 can  be  used	repeatedly  to
       cycle through the list of windows.

       nonblock	[on|off|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 con-
       nection gets cut	but no hangup is received. If nonblock is off (this is
       the default) screen waits until the display restarts to accept the out-
       put.  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.

       number [n]

       Change  the  current  windows  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.

       obuflimit [limit]

       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.

       only

       Kill all	regions	but the	current	one.

       other

       Switch  to  the	window	displayed  previously.	If this	window does no
       longer exist, other has the same	effect as next.

       partial on|off

       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.

       password	[crypted_pw]

       Present a crypted password in your ".screenrc" file and screen will ask
       for  it,	whenever someone attempts to resume a detached.	This is	useful
       if you have privileged programs running under screen and	 you  want  to
       protect	your session from reattach attempts by another user masquerad-
       ing as your uid (i.e. any superuser.)  If no crypted password is	speci-
       fied, screen prompts twice for typing a password	and places its encryp-
       tion in the paste buffer.  Default is `none',  this  disables  password
       checking.

       paste [registers	[dest_reg]]

       Write  the  (concatenated)  contents  of	the specified registers	to the
       stdin queue of the current window. The register '.' is treated  as  the
       paste  buffer. If no parameter is given the user	is prompted for	a sin-
       gle register to paste.  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  displays  paste buffer is the destination.
       Note, that "paste" uses a wide variety of resources: 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.

       pastefont [on|off]

       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.

       pow_break

       Reopen the window's terminal line  and  send  a	break  condition.  See
       `break'.

       pow_detach

       Power  detach.  Mainly the same as detach, but also sends a HANGUP sig-
       nal to the parent process of screen.  CAUTION: This will	 result	 in  a
       logout, when screen was started from your login shell.

       pow_detach_msg [message]

       The message specified here is output whenever a `Power detach' was per-
       formed. It may be used as a replacement for  a  logout  message	or  to
       reset baud rate,	etc.  Without parameter, the current message is	shown.

       prev

       Switch to the window with the next lower	number.	 This command  can  be
       used repeatedly to cycle	through	the list of windows.

       printcmd	[cmd]

       If  cmd	is not an empty	string,	screen will not	use the	terminal capa-
       bilities	"po/pf"	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 a	command	 displays  the
       current	setting.  The ansi sequence ESC	\ 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.

       process [key]

       Stuff the contents of the specified register into screen's 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.

       quit

       Kill all	windows	and terminate screen.  Note that on VT100-style	termi-
       nals  the keys C-4 and C-\ are identical.  This makes the default bind-
       ings dangerous: Be careful not to type C-a C-4  when  selecting	window
       no.  4.	Use the	empty bind command (as in "bind	'^\'") to remove a key
       binding.

       readbuf [-e encoding] [filename]

       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.  See	also  "buffer-
       file" command.

       readreg [-e encoding] [register [filename]]

       Does  one of two	things,	dependent on number of arguments: with zero or
       one arguments it	it duplicates the paste	buffer contents	into the  reg-
       ister  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

       redisplay

       Redisplay the current window. Needed to get a full  redisplay  when  in
       partial redraw mode.

       register	[-e encoding] key string

       Save  the  specified  string  to	the register key.  The encoding	of the
       string can be specified via the -e option.  See also the	 "paste"  com-
       mand.

       remove

       Kill the	current	region.	This is	a no-op	if there is only one region.

       removebuf

       Unlinks	the  screen-exchange  file used	by the commands	"writebuf" and
       "readbuf".

       reset

       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.

       resize

       Resize the current region. The space will be removed from or  added  to
       the  region below or if there's not enough space	from the region	above.

	      resize +N	  increase current region height by N

	      resize -N	  decrease current region height by N

	      resize  N	  set current region height to N

	      resize  =	  make all windows equally high

	      resize  max maximize current region height

	      resize  min minimize current region height

       screen [-opts] [n] [cmd [args]]

       Establish a new window.	The flow-control options (-f,  -fn  and	 -fa),
       title  (a.k.a.) 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..9 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 com-
       mand is specified after "screen", this command (with  the  given	 argu-
       ments)  is started in the window; otherwise, a shell is created.	 Thus,
       if your ".screenrc" contains the	lines

		   # example for .screenrc:
		   screen 1
		   screen -fn -t foobar	-L 2 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.	Note, that unlike previous versions of screen no addi-
       tional default window is	created	when "screen" commands are included in
       your  ".screenrc"  file.	 When  the initialization is completed,	screen
       switches	to the last window specified in	your  .screenrc	 file  or,  if
       none, opens a default window #0.
       Screen  has built in some functionality of "cu" and "telnet".  See also
       chapter "WINDOW TYPES".

       scrollback num

       Set the size of the scrollback buffer for the current  windows  to  num
       lines.  The  default scrollback is 100 lines.  See also the "defscroll-
       back" command and use "C-a i" to	view the current setting.

       select [WindowID]

       Switch to the window identified by WindowID.  This can be a prefix of a
       window title (alphanumeric window name) or a window number.  The	param-
       eter is optional	and if omitted,	you get	prompted  for  an  identifier.
       When  a	new  window  is	 established,  the  first  available number is
       assigned	to this	window.	 Thus, the first window	can  be	 activated  by
       "select	0".   The  number of windows is	limited	at compile-time	by the
       MAXWIN configuration parameter.	There are two special  WindowIDs,  "-"
       selects	the  internal blank window and "." selects the current window.
       The latter is useful if used with screen's "-X" option.

       sessionname [name]

       Rename the current session. Note, that  for  "screen  -list"  the  name
       shows up	with the process-id prepended. If the argument "name" is omit-
       ted, the	name of	this session is	displayed. Caution: The	$STY  environ-
       ment  variables	still reflects the old name. This may result in	confu-
       sion.  The default is constructed from the tty and host names.

       setenv [var [string]]

       Set the environment variable var	to value string.  If only var is spec-
       ified,  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.

       setsid [on|off]

       Normally	screen uses different sessions and process groups for the win-
       dows. If	setsid is turned off, this is not done anymore and all windows
       will  be	 in the	same process group as the screen backend process. This
       also breaks job-control,	so be careful.	The default is on, of  course.
       This command is probably	useful only in rare circumstances.

       shell command

       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	speci-
       fied in $SHELL. If the command begins with a '-'	character,  the	 shell
       will be started as a login-shell.

       shelltitle title

       Set  the	 title for all shells created during startup or	by the C-A C-c
       command.	 For details about what	a title	is, see	the  discussion	 enti-
       tled "TITLES (naming windows)".

       silence [on|off|sec]

       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.

       silencewait sec

       Define the time that all	windows	 monitored  for	 silence  should  wait
       before displaying a message. Default 30 seconds.

       sleep num

       This  command will pause	the execution of a .screenrc file for num sec-
       onds.  Keyboard activity	will end the sleep.  It	may be	used  to  give
       users a chance to read the messages output by "echo".

       slowpaste msec

       Define  the  speed at which text	is inserted into the current window by
       the paste ("C-a ]") command.  If	the slowpaste value is nonzero text is
       written	character by character.	 screen	will make a pause of msec mil-
       liseconds after each single character write to allow the	application to
       process its input. Only use slowpaste if	your underlying	system exposes
       flow control problems while pasting large amounts of text.

       source file

       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 com-
       mand 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.

       sorendition [attr [color]]

       Change the way screen does highlighting for text	marking	 and  printing
       messages.  See the "STRING ESCAPES" chapter for the syntax of the modi-
       fiers.  The default is currently	"=s dd"	(standout, default colors).

       split

       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 dis-
       played on the new region. Use the "remove" or  the  "only"  command  to
       delete regions.

       startup_message on|off

       Select  whether	you  want  to see the copyright	notice during startup.
       Default is `on',	as you probably	noticed.

       stuff string

       Stuff the string	string in the input  buffer  of	 the  current  window.
       This is like the	"paste"	command	but with much less overhead.  You can-
       not paste large buffers with the	"stuff"	command. It is most useful for
       key bindings. See also "bindkey".

       su [username [password [password2]]

       Substitute  the	user of	a display. The command prompts for all parame-
       ters that are omitted. If passwords are specified as  parameters,  they
       have  to	be specified un-crypted. The first password is matched against
       the systems passwd database, the	second password	is matched against the
       screen  password	as set with the	commands "acladd" or "password".  "Su"
       may be useful for the screen administrator to  test  multiuser  setups.
       When  the  identification  fails,  the  user has	access to the commands
       available for user nobody.  These are "detach",	"license",  "version",
       "help" and "displays".

       suspend

       Suspend	screen.	 The windows are in the	`detached' state, while	screen
       is suspended. This feature relies on the	shell being  able  to  do  job
       control.

       term term

       In each window's	environment screen opens, the $TERM variable is	set to
       "screen"	by default.  But when no description for "screen" is installed
       in  the	local  termcap or terminfo data	base, you set $TERM to - say -
       "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.

       termcap term terminal-tweaks [window-tweaks]
       terminfo	term terminal-tweaks [window-tweaks]
       termcapinfo term	terminal-tweaks	[window-tweaks]

       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 win-
       dows.  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	 works 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 interpo-
       lation (using `%') is required. Note that termcap names of the capabil-
       ities have to be	used with the `terminfo' command.
       In many cases, where the	arguments are valid in both terminfo and term-
       cap  syntax,  you  can  use  the	command	`termcapinfo', which is	just a
       shorthand for a pair of `termcap' and `terminfo'	commands with  identi-
       cal 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 win-
       dow termcaps, and should	contain	definitions  that  screen  understands
       (see the	"VIRTUAL TERMINAL" section).

       Some examples:

	      termcap xterm*  LP: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
       (LP), but they don't really have	a status line (no 'hs' - append	`@' to
       turn entries off).  Note	that we	assume `LP'  for  all  terminal	 names
       that  start  with "vt", but only	if you don't specify a termcap command
       for that	terminal.

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

       Specifies the firm-margined `LP'	 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  the	 discussion  on	the "VIRTUAL TERMINAL" in this manual, and the
       termcap(5) man page for more information	on termcap definitions.

       time [string]

       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".

       If a string is specified, it changes the	format of the time report like
       it  is described	in the "STRING ESCAPES"	chapter. Screen	uses a default
       of "%c:%s %M %d %H%? %l%?".

       title [windowtitle]

       Set the name of the current window to windowtitle. If no	name is	speci-
       fied, screen prompts for	one. This command was known as `aka' in	previ-
       ous releases.

       unsetenv	var

       Unset an	environment variable.

       utf8 [on|off [on|off]]

       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. Omit-
       ting 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.

       vbell [on|off]

       Sets  the  visual  bell setting for this	window.	Omitting the parameter
       toggles the setting. If vbell is	switched on, but  your	terminal  does
       not support a visual bell, a `vbell-message' is displayed in the	status
       line when the bell character (^G) is received.  Visual bell support  of
       a terminal is defined by	the termcap variable `vb' (terminfo: 'flash').
       Per default, vbell is off, thus the audible bell	 is  used.   See  also
       `bell_msg'.

       vbell_msg [message]

       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",  but
       the  terminal  does  not	support	a visual bell.	The default message is
       "Wuff, Wuff!!".	Without	parameter, the current message is shown.

       vbellwait sec

       Define a	delay in seconds after each display of	screen's  visual  bell
       message.	The default is 1 second.

       verbose [on|off]

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

       version

       Print the current version and the compile date in the status line.

       wall message

       Write  a	message	to all displays. The message will appear in the	termi-
       nal's status line.

       width [-w|-d] [cols [lines]]

       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  for
       more  information.  You	can  also  specify a new 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.

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

       Display all windows in a	table for visual window	selection. The desired
       window can be selected via the standard movement	keys (see  the	"copy"
       command)	 and activated via the return key.  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  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
       for more	codes (e.g. color settings).

       windows

       Uses  the message line to display a list	of all the windows.  Each win-
       dow is listed by	number with the	name of	process	that has been  started
       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  `$';	 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 `@'; a	window
       which has output	logging	turned on is marked with `(L)';	windows	 occu-
       pied  by	 other	users are marked with `&'; 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.

       wrap [on|off]

       Sets  the  line-wrap setting for	the current window.  When line-wrap is
       on, the second consecutive printable character output at	the last  col-
       umn  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'.

       writebuf	[-e encoding] [filename]

       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.  The filename can be set with
       the bufferfile command and defaults to "/tmp/screen-exchange".

       writelock [on|off|auto]

       In addition to access control lists, not	all users may be able to write
       to  the	same  window at	once. Per default, writelock is	in `auto' mode
       and grants exclusive input permission to	the user who is	the  first  to
       switch to the particular	window.	When he	leaves the window, other users
       may obtain the writelock	(automatically). The writelock of the  current
       window  is  disabled by the command "writelock off". If the user	issues
       the command "writelock on" he  keeps  the  exclusive  write  permission
       while switching to other	windows.

       xoff
       xon

       Insert  a  CTRL-s  / CTRL-q character to	the stdin queue	of the current
       window.

       zmodem [off|auto|catch|pass]
       zmodem sendcmd [string]
       zmodem recvcmd [string]

       Define zmodem support for  screen.  Screen  understands	two  different
       modes  when  it	detects	 a zmodem request: "pass" and "catch".	If the
       mode is set to "pass", screen will relay	all data to the	attacher until
       the end of the transmission is reached.	In "catch" mode	screen acts as
       a zmodem	endpoint and starts the	corresponding rz/sz commands.  If  the
       mode  is	 set to	"auto",	screen will use	"catch"	if the window is a tty
       (e.g. a serial line), otherwise it will use "pass".
       You can define the templates screen uses	in "catch" mode	via the	second
       and the third form.
       Note also that this is an experimental feature.

       zombie [keys]
       defzombie [keys]

       Per  default screen 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 such a  window.  Pressing
       the first key in	the dead window	has the	same effect. When pressing the
       second key, screen will attempt to resurrect the	 window.  The  process
       that  was initially running in the window will be launched again. Call-
       ing zombie without parameters will clear	the zombie setting, thus  mak-
       ing windows disappear when their	process	exits.

       As  the	zombie-setting	is  manipulated	globally for all windows, this
       command should only be called defzombie.	Until we need this  as	a  per
       window setting, the commands zombie and defzombie are synonymous.

THE MESSAGE LINE
       Screen  displays	informational messages and other diagnostics in	a mes-
       sage line.  While this line is distributed to appear at the  bottom  of
       the screen, it can be defined to	appear at the top of the screen	during
       compilation.  If	your terminal has a status line	defined	in  its	 term-
       cap, screen will	use this for displaying	its messages, otherwise	a line
       of the current screen will be temporarily overwritten and  output  will
       be  momentarily	interrupted. The message line is automatically removed
       after a few seconds delay, but it can also be removed early (on	termi-
       nals without a status line) by beginning	to type.

       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 '<esc>^Hello	world from window '$WINDOW'<esc>\\'

       where  '<esc>'  is an escape, '^' is a literal up-arrow,	and '\\' turns
       into a single backslash.

WINDOW TYPES
       Screen provides three different window types. New windows  are  created
       with screen's screen command (see also the entry	in chapter "CUSTOMIZA-
       TION"). 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 multiplexer with 100 or more windows.

       o  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...)

       o  If a tty (character special device) name (e.g. "/dev/ttya") is spec-
	  ified	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.

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

	  ixoff	or -ixon
		 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 parame-
	  ter values of	the connection.	 These values are system dependant 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',
	  `DSR',  `CD'	and more.  This	depends	on the available ioctl()'s and
	  system header	files as well as the on	the physical  capabilities  of
	  the  serial  board.	Signals	 that  are logical low (inactive) have
	  their	name preceded by an exclamation	mark (!), otherwise the	signal
	  is logical high (active).  Signals not supported by the hardware but
	  available to the ioctl() interface 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 TIOC-
	  SOFTCAR bit is set, the signals `CTS'	or `CD'	are shown in parenthe-
	  sis, 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.

       o  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 connec-
	  tion 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 oth-
		 erwise	(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.

	  This window type is only available if	screen was compiled  with  the
	  BUILTIN_TELNET option	defined.

STRING ESCAPES
       Screen provides an escape mechanism to insert information like the cur-
       rent time into messages or file names. The escape character is '%' with
       one  exception:	inside	of  a  window's	hardstatus '^%'	('^E') is used
       instead.

       Here is the full	list of	supported escapes:

       %      the escape character itself

       a      either 'am' or 'pm'

       A      either 'AM' or 'PM'

       c      current time HH:MM in 24h	format

       C      current time HH:MM in 12h	format

       d      day number

       D      weekday name

       f      flags of the window

       F      sets %? to true if the window has	the focus

       h      hardstatus of the	window

       H      hostname of the system

       l      current load of the system

       m      month number

       M      month name

       n      window number

       s      seconds

       t      window title

       u      all other	users on this window

       w      all window numbers and names. With '-'  quailifier:  up  to  the
	      current  window;	with  '+'  qualifier: starting with the	window
	      after the	current	one.

       W      all window numbers and names except the current one

       y      last two digits of the year number

       Y      full year	number

       ?      the part to the next '%?'	is displayed  only  if	a  '%'	escape
	      inside the part expands to a non-empty string

       :      else part	of '%?'

       =      pad  the	string to the display's	width (like TeX's hfill). If a
	      number is	specified, pad	to  the	 percentage  of	 the  window's
	      width.   A  '0'  qualifier  tells	 screen	to treat the number as
	      absolute position.  You can specify to pad relative to the  last
	      absolute	pad position by	adding a '+' qualifier or to pad rela-
	      tive to the right	margin by using	'-'. The padding truncates the
	      string  if  the specified	position lies before the current posi-
	      tion. Add	the 'L'	qualifier to change this.

       <      same as '%=' but just do truncation, do not fill with spaces

       >      mark the current text position for  the  next  truncation.  When
	      screen  needs  to	do truncation, it tries	to do it in a way that
	      the marked position gets moved to	the  specified	percentage  of
	      the  output  area.  (The	area starts from the last absolute pad
	      position and ends	with the position specified by the  truncation
	      operator.)  The 'L' qualifier tells screen to mark the truncated
	      parts with '...'.

       {      attribute/color modifier string terminated by the	next "}"

       `      Substitute with the output of a 'backtick' command.  The	length
	      qualifier	is misused to identify one of the commands.

       The  'c'	 and 'C' escape	may be qualified with a	'0' to make screen use
       zero instead of space as	fill character.	The '0'	qualifier  also	 makes
       the  '='	 escape	use absolute positions.	The 'n'	and '='	escapes	under-
       stand a length qualifier	(e.g. '%3n'), 'D' and 'M' can be prefixed with
       'L'  to	generate long names, 'w' and 'W' also show the window flags if
       'L' is given.

       An attribute/color modifier is is used to change	the attributes or  the
       color  settings.	 Its  format  is "[attribute modifier] [color descrip-
       tion]". The attribute modifier must be prefixed by a change type	 indi-
       cator  if  it  can  be  confused	with a color desciption. The following
       change types are	known:

       +      add the specified	set to the current attributes

       -      remove the set from the current attributes

       !      invert the set in	the current attributes

       =      change the current attributes to the specified set

       The attribute set can either be specified as a hexadecimal number or  a
       combination of the following letters:

       d      dim
       u      underline
       b      bold
       r      reverse
       s      standout
       B      blinking

       Colors are coded	either as a hexadecimal	number or two letters specify-
       ing the desired background and foreground color (in  that  order).  The
       following colors	are known:

       k      black
       r      red
       g      green
       y      yellow
       b      blue
       m      magenta
       c      cyan
       w      white
       d      default color
       .      leave color unchanged

       The  capitalized	 versions of the letter	specify	bright colors. You can
       also use	the pseudo-color 'i' to	set just the brightness	and leave  the
       color unchanged.
       A  one digit/letter color description is	treated	as foreground or back-
       ground color dependant on the current attributes: if  reverse  mode  is
       set,  the  background color is changed instead of the foreground	color.
       If you don't like this, prefix the color	with a ".". If	you  want  the
       same behaviour for two-letter color descriptions, also prefix them with
       a ".".
       As a special case, "%{-}" restores the attributes and colors that  were
       set  before the last change was made (i.e. pops one level of the	color-
       change stack).

       Examples:

       "G"    set color	to bright green

       "+b r" use bold red

       "= yd" clear all	attributes, write in default  color  on	 yellow	 back-
	      ground.

       %-Lw%{= BW}%50>%n%f* %t%{-}%+Lw%<
	      The  available  windows centered at the current window and trun-
	      cated to the available width. The	current	 window	 is  displayed
	      white  on	 blue.	 This can be used with "hardstatus alwayslast-
	      line".

       %?%F%{.R.}%?%3n %t%? [%h]%?
	      The window number	and title and the window's hardstatus, if  one
	      is  set.	Also use a red background if this is the active	focus.
	      Useful for "caption string".

FLOW-CONTROL
       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	 char-
       acters,	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" pro-
       gram 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"	.screenrc command. Per 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	find out 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 "inter-
       rupt" 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 it is possible  to	interrupt  the
       output of the virtual terminal to your physical terminal	when flow-con-
       trol is enabled.	 If this happens, 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.

TITLES (naming windows)
       You can customize each window's name in the window display (viewed with
       the "windows" command (C-a w)) by setting it with one of	the title com-
       mands.  Normally	the name displayed is the actual command name  of  the
       program created in the window.  However,	it is sometimes	useful to dis-
       tinguish	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 in the .screenrc	file, while all	other windows are created with
       a "screen" command and thus can have their name set with	the -t option.
       Interactively,	 there	  is	the    title-string    escape-sequence
       (<esc>kname<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 pre-defined names to keys with	the  "title"  command  to  set
       things quickly without prompting.

       Finally,	 screen	has a shell-specific heuristic that is enabled by set-
       ting the	window's name to "search|name" and arranging to	 have  a  null
       title escape-sequence output as a part of your prompt.  The search por-
       tion specifies an end-of-prompt search string, while the	 name  portion
       specifies the default shell name	for the	window.	 If the	name ends in a
       `:' screen will add what	it believes to be the current command  running
       in  the window to the end of the	window's shell name (e.g. "name:cmd").
       Otherwise the current command name supersedes the shell name  while  it
       is running.

       Here's  how  it	works:	 you must modify your shell prompt to output a
       null title-escape-sequence (<esc>k<esc>\) as a  part  of	 your  prompt.
       The  last part of your prompt must be the same as the string you	speci-
       fied for	the search portion of the title.  Once this is set up,	screen
       will  use  the title-escape-sequence to clear the previous command name
       and get ready for the next command.  Then, when a newline  is  received
       from  the shell,	a search is made for the end of	the prompt.  If	found,
       it will grab the	first word after the matched string and	use it as  the
       command	name.  If the command name begins with either '!', '%',	or '^'
       screen will use the first word on the  following	 line  (if  found)  in
       preference  to  the  just-found	name.  This helps csh users get	better
       command names when using	job control or history recall commands.

       Here's some .screenrc examples:

	      screen -t	top 2 nice top

       Adding this line	to your	.screenrc would	start a	nice-d version of  the
       "top" command in	window 2 named "top" rather than "nice".

		   shelltitle '> |csh'
		   screen 1

       These  commands	would  start  a	 shell with the	given shelltitle.  The
       title specified is an auto-title	that would expect the prompt  and  the
       typed command to	look something like the	following:

	      /usr/joe/src/dir>	trn

       (it  looks  after  the  '>  ' for the command name).  The window	status
       would show the name "trn" while the command was running,	and revert  to
       "csh" upon completion.

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

       Having  this command in your .screenrc would bind the key sequence "C-a
       R" to the "su" command and give it an auto-title	name of	"root:".   For
       this auto-title to work,	the screen could look something	like this:

		   % !em
		   emacs file.c

       Here  the user typed the	csh history command "!em" which	ran the	previ-
       ously  entered  "emacs"	command.   The	window	 status	  would	  show
       "root:emacs"  during the	execution of the command, and revert to	simply
       "root:" at its completion.

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

       The first binding doesn't have any arguments, so	it  would  prompt  you
       for  a title. when you type "C-a	o".  The second	binding	would clear an
       auto-title's current setting (C-a E).  The third	binding	would set  the
       current window's	title to "(unknown)" (C-a u).

       One  thing  to keep in mind when	adding a null title-escape-sequence to
       your prompt is that some	shells (like the csh) count all	 the  non-con-
       trol  characters	 as  part  of the prompt's length.  If these invisible
       characters aren't a multiple of 8 then  backspacing  over  a  tab  will
       result in an incorrect display.	One way	to get around this is to use a
       prompt like this:

	      set prompt='^[[0000m^[k^[\% '

       The escape-sequence "<esc>[0000m" not  only  normalizes	the  character
       attributes, but all the zeros round the length of the invisible charac-
       ters up to 8.  Bash  users  will	 probably  want	 to  echo  the	escape
       sequence	in the PROMPT_COMMAND:

	      PROMPT_COMMAND='echo -n -e "\033k\033\134"'

       (I used "134" to	output a `\' because of	a bug in bash v1.04).

THE VIRTUAL TERMINAL
       Each  window  in	 a screen session emulates a VT100 terminal, with some
       extra functions added. The VT100	emulator is hard-coded,	no other  ter-
       minal types can be emulated.
       Usually	screen	tries to emulate as much of the	VT100/ANSI standard as
       possible. But if	your terminal lacks certain capabilities,  the	emula-
       tion  may not be	complete. In these cases screen	has to tell the	appli-
       cations 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	impor-
       tant  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	 term-
       cap/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. Notice that, however, on
       machines	using the terminfo database this variable has no effect.  Fur-
       thermore, the variable $WINDOW is set to	the window number of each win-
       dow.

       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 capabili-
       ties  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"  .screenrc  command,  or  by defining the variable $SCREENCAP
       prior to	startup.  When the is 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" .screenrc command if the	system
       uses the	terminfo database rather than termcap.

       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 sup-
       ported:	lock  shift  G0	 (SI), lock shift G1 (SO), lock	shift G2, lock
       shift G3, single	shift G2, and single shift G3.	When a virtual	termi-
       nal  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 capabil-
       ity.

       When the	`po' and `pf' capabilities are present in the terminal's term-
       cap  entry,  applications running in a screen window can	send output to
       the printer port	of the terminal.  This allows a	user to	have an	appli-
       cation  in one window sending output to a printer connected to the ter-
       minal, 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 `PRIN' while the
       printer is active.

       Screen  maintains  a hardstatus line for	every window. If a window gets
       selected, the display's hardstatus will be updated to  match  the  win-
       dow's  hardstatus  line.	If the display has no hardstatus the line will
       be displayed as a standard screen message.  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.

       Some  capabilities  are only put	into the $TERMCAP variable of the vir-
       tual terminal if	they can be efficiently	implemented  by	 the  physical
       terminal.  For instance,	`dl' (delete line) is only put into the	$TERM-
       CAP variable if the terminal supports  either  delete  line  itself  or
       scrolling  regions. Note	that this may provoke confusion, when the ses-
       sion is reattached on a different terminal, as the  value  of  $TERMCAP
       cannot be modified by parent processes.

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

       The following is	a list of  control  sequences  recognized  by  screen.
       "(V)" and "(A)" indicate	VT100-specific and ANSI- or ISO-specific func-
       tions, 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			  A.k.a. Definition String

       ESC P		     (A)  Device Control  String.   Outputs  a	string
				  directly to the host terminal	without	inter-
				  pretation.

       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	 :win-
				  dow:	-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			  Send Terminal	Parameter Report

       ESC [ > c		  Send	 VT220	 Secondary  Device  Attributes
				  String

       ESC [ 6 n		  Send Cursor Position Report

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	 stan-
       dard  VT100  emulation  the  command will always	insert a string	in the
       input buffer of the window (see also command stuff in the  command  ta-
       ble).  Because the sequences generated by a keypress can	change after a
       reattach	from a different terminal type,	it is possible	to  bind  com-
       mands  to the termcap name of the keys.	Screen will insert the correct
       binding after each  reattach.  See  the	bindkey	 command  for  further
       details on the syntax and examples.

       Here  is	the table of the default key bindings. (A) means that the com-
       mand 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)

SPECIAL	TERMINAL CAPABILITIES
       The following table describes all terminal capabilities that are	recog-
       nized  by  screen  and are not in the termcap(5)	manual.	 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 because screen  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 back to normal mode.

       AN   (bool)  Turn on autonuke. See  the	'autonuke'  command  for  more
		    details.

       OL   (num)   Set	 the  output buffer limit. See the 'obuflimit' command
		    for	more details.

       KJ   (str)   Set	the encoding of	the terminal. See the 'encoding'  com-
		    mand 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. More details follow in the next sec-
		    tion.

       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).

CHARACTER TRANSLATION
       Screen  has  a  powerful	mechanism to translate characters to arbitrary
       strings depending on the	current	font and terminal type.	 Use this fea-
       ture  if	 you  want  to	work with a common standard character set (say
       ISO8851-latin1) even on terminals that scatter the more unusual charac-
       ters 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 _desig-
       nator_ ('B': Ascii, 'A':	UK, 'K':  german,  etc.)   to  strings.	 Every
       _mapping_  describes  to	 what string a single character	will be	trans-
       lated. 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  spe-
       cial 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,	there-
       fore 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 when-
       ever 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'.

ENVIRONMENT
       COLUMNS	      Number  of  columns  on  the terminal (overrides termcap
		      entry).
       HOME	      Directory	in which to look for .screenrc.
       LINES	      Number of	 lines	on  the	 terminal  (overrides  termcap
		      entry).
       LOCKPRG	      Screen lock program.
       NETHACKOPTIONS Turns on nethack option.
       PATH	      Used for locating	programs to run.
       SCREENCAP      For customizing a	terminal's TERMCAP value.
       SCREENDIR      Alternate	socket directory.
       SCREENRC	      Alternate	user screenrc file.
       SHELL	      Default  shell  program  for  opening  windows  (default
		      "/bin/sh").
       STY	      Alternate	socket name.
       SYSSCREENRC    Alternate	system screenrc	file.
       TERM	      Terminal name.
       TERMCAP	      Terminal description.
       WINDOW	      Window number of a window	(at creation time).

FILES
       .../screen-4.?.??/etc/screenrc
       .../screen-4.?.??/etc/etcscreenrc Examples in the  screen  distribution
					 package  for  private and global ini-
					 tialization files.
       $SYSSCREENRC
       /usr/local/etc/screenrc		 screen	initialization commands
       $SCREENRC
       $HOME/.screenrc			 Read in after /usr/local/etc/screenrc
       $SCREENDIR/S-<login>
       /local/screens/S-<login>		 Socket	directories (default)
       /usr/tmp/screens/S-<login>	 Alternate socket directories.
       <socket directory>/.termcap	 Written by the	"termcap" output func-
					 tion
       /usr/tmp/screens/screen-exchange	 or
       /tmp/screen-exchange		 screen	 `interprocess	 communication
					 buffer'
       hardcopy.[0-9]			 Screen	images created by the hardcopy
					 function
       screenlog.[0-9]			 Output	log files created by  the  log
					 function
       /usr/lib/terminfo/?/*		 or
       /etc/termcap			 Terminal capability databases
       /etc/utmp			 Login records
       $LOCKPRG				 Program that locks a terminal.

SEE ALSO
       termcap(5), utmp(5), vi(1), captoinfo(1), tic(1)

AUTHORS
       Originally  created by Oliver Laumann, this latest version was produced
       by Wayne	Davison, Juergen Weigert and Michael Schroeder.

COPYLEFT
       Copyright (C) 1993-2003
	    Juergen Weigert (jnweiger@immd4.informatik.uni-erlangen.de)
	    Michael Schroeder (mlschroe@immd4.informatik.uni-erlangen.de)
       Copyright (C) 1987 Oliver Laumann
       This program is free software; you can redistribute it and/or modify it
       under  the  terms of the	GNU General Public License as published	by the
       Free Software Foundation; either	version	2, or  (at  your  option)  any
       later version.
       This  program  is  distributed  in the hope that	it will	be useful, but
       WITHOUT ANY  WARRANTY;  without	even  the  implied  warranty  of  MER-
       CHANTABILITY  or	FITNESS	FOR A PARTICULAR PURPOSE.  See the GNU General
       Public License for more details.
       You should have received	a copy of the GNU General Public License along
       with  this  program  (see  the file COPYING); if	not, write to the Free
       Software	Foundation, Inc., 59 Temple Place  -  Suite  330,  Boston,  MA
       02111-1307, USA

CONTRIBUTORS
       Ken Beal	(kbeal@amber.ssd.csd.harris.com),
       Rudolf Koenig (rfkoenig@immd4.informatik.uni-erlangen.de),
       Toerless	Eckert (eckert@immd4.informatik.uni-erlangen.de),
       Wayne Davison (davison@borland.com),
       Patrick Wolfe (pat@kai.com, kailand!pat),
       Bart Schaefer (schaefer@cse.ogi.edu),
       Nathan Glasser (nathan@brokaw.lcs.mit.edu),
       Larry W.	Virden (lvirden@cas.org),
       Howard Chu (hyc@hanauma.jpl.nasa.gov),
       Tim MacKenzie (tym@dibbler.cs.monash.edu.au),
       Markku Jarvinen (mta@{cc,cs,ee}.tut.fi),
       Marc Boucher (marc@CAM.ORG),
       Doug Siebert (dsiebert@isca.uiowa.edu),
       Ken Stillson (stillson@tsfsrv.mitre.org),
       Ian Frechett (frechett@spot.Colorado.EDU),
       Brian Koehmstedt	(bpk@gnu.ai.mit.edu),
       Don Smith (djs6015@ultb.isc.rit.edu),
       Frank van der Linden (vdlinden@fwi.uva.nl),
       Martin Schweikert (schweik@cpp.ob.open.de),
       David Vrona (dave@sashimi.lcu.com),
       E. Tye McQueen (tye%spillman.UUCP@uunet.uu.net),
       Matthew Green (mrg@eterna.com.au),
       Christopher Williams (cgw@pobox.com),
       Matt Mosley (mattm@access.digex.net),
       Gregory Neil Shapiro (gshapiro@wpi.WPI.EDU),
       Johannes	Zellner	(johannes@zellner.org),
       Pablo Averbuj (pablo@averbuj.com).

VERSION
       This is version 4.0.2. Its roots	are a merge of a custom	version	2.3PR7
       by Wayne	Davison	and several enhancements to Oliver  Laumann's  version
       2.0.  Note  that	all versions numbered 2.x are copyright	by Oliver Lau-
       mann.

AVAILABILITY
       The latest official release of screen available via anonymous ftp  from
       gnudist.gnu.org,	 nic.funet.fi  or any other GNU	distribution site. The
       home site of screen is ftp.uni-erlangen.de, in the directory pub/utili-
       ties/screen.  The subdirectory `private'	contains the latest beta test-
       ing release. If you want	to help,  send	a  note	 to  screen@uni-erlan-
       gen.de.

BUGS
       o  `dm'	(delete	 mode)	and  `xs'  are not handled correctly (they are
	  ignored). `xn' is treated as a magic-margin indicator.

       o  Screen has no	clue about double-high or double-wide characters.  But
	  this is the only area	where vttest is	allowed	to fail.

       o  It  is not possible to change	the environment	variable $TERMCAP when
	  reattaching under a different	terminal type.

       o  The support of terminfo based	systems	is very	limited. Adding	 extra
	  capabilities to $TERMCAP may not have	any effects.

       o  Screen does not make use of hardware tabs.

       o  Screen  must be installed as set-uid with owner root on most systems
	  in order to be able to correctly change the owner of the tty	device
	  file	for  each  window.  Special permission may also	be required to
	  write	the file "/etc/utmp".

       o  Entries in "/etc/utmp" are not removed when screen  is  killed  with
	  SIGKILL.   This  will	 cause	some  programs (like "w" or "rwho") to
	  advertise that a user	is logged on who really	isn't.

       o  Screen may give a strange warning when your tty has no utmp entry.

       o  When the modem line was hung up, screen may not automatically	detach
	  (or  quit)  unless  the device driver	is configured to send a	HANGUP
	  signal.  To detach a screen session use the -D or  -d	 command  line
	  option.

       o  If  a	 password  is  set,  the  command line options -d and -D still
	  detach a session without asking.

       o  Both "breaktype" and	"defbreaktype"	change	the  break  generating
	  method  used by all terminal devices.	The first should change	a win-
	  dow specific setting,	 where	the  latter  should  change  only  the
	  default for new windows.

       o  When	attaching to a multiuser session, the user's .screenrc file is
	  not sourced. Each user's personal settings have to  be  included  in
	  the  .screenrc  file from which the session is booted, or have to be
	  changed manually.

       o  A weird imagination is most useful to	gain full advantage of all the
	  features.

       o  Send bug-reports, fixes, enhancements, t-shirts, money, beer & pizza
	  to screen@uni-erlangen.de.

4th Berkeley Distribution	   Aug 2003			     SCREEN(1)

NAME | SYNOPSIS | DESCRIPTION | GETTING STARTED | COMMAND-LINE OPTIONS | DEFAULT KEY BINDINGS | CUSTOMIZATION | THE MESSAGE LINE | WINDOW TYPES | STRING ESCAPES | FLOW-CONTROL | TITLES (naming windows) | THE VIRTUAL TERMINAL | INPUT TRANSLATION | SPECIAL TERMINAL CAPABILITIES | CHARACTER TRANSLATION | ENVIRONMENT | FILES | SEE ALSO | AUTHORS | COPYLEFT | CONTRIBUTORS | VERSION | AVAILABILITY | BUGS

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