screen



SCREEN(1)                   General Commands Manual                  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
       terminal 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
       output 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
       visible 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
       window.  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
       creates a new window running a shell and switches to that window
       immediately, 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
       environment 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 "/var/run/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",
       "shutdown", "rsend", "sccs" and other similar programs that use the
       utmp file to determine who you are. As long as screen is active on your
       terminal, 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
       correctly 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
            window'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
            terminal.  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
               running, 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
            sessions by means of "screen -list".

       -e xy
            specifies the command character to be x and the character
            generating 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
            display immediately when flow-control is on.  See the "defflow"
            .screenrc command for details.  The use of this option is
            discouraged.

       -l and -ln
            turns login mode on or off (for /var/run/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
            system 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
            sessions. 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
            combinations 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
            program.  See also the "shelltitle" .screenrc command.

       -U   Run screen in UTF-8 mode. This option tells screen that your
            terminal 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
            considered 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
       counterparts (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
       "CUSTOMIZATION" 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
                                 command character typed twice, unless
                                 overridden.  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
                                 current 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
                                 message 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
                                 displays.


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 "/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
       beginning of your screen session.  Commands are listed one per line,
       with empty lines being ignored.  A command's arguments are separated by
       tabs or spaces, and may be surrounded by single or double quotes.  A
       `#' turns the rest of the line into a comment, except in quotes.
       Unintelligible lines are warned about and ignored.  Commands may
       contain references to environment variables. The syntax is the shell-
       like "$VAR " or "${VAR}". Note that this causes incompatibility with
       previous screen versions, as now the '$'-character has to be protected
       with '\' if no variable substitution shall be performed. A string in
       single-quotes is also protected from variable substitution.

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

       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
       permission, `-' removes it. The third parameter is a comma separated
       list of commands and/or windows (specified either by number or title).
       The special 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 windows. 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
       created 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
       special username "?" predefines the access that not yet known users
       will be granted to any window initially.  The special username "??"
       predefines 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
       monitored, screen displays a notification in the message line.  The
       notification message can be re-defined by means of the "activity"
       command.  Each occurrence of `%' in message is replaced by the number
       of the window in which activity has occurred, and each occurrence of
       `^G' is replaced by the definition for bell in your termcap (usually an
       audible bell).  The default message is

                   'Activity in window %n'

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

       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
       terminals, 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
       `current display' setting) of the command. If the first parameter
       describes a non-unique context, the command will be executed multiple
       times. If the first parameter is of the form `identifier*' then
       identifier is matched against user names.  The command is executed once
       for each display of the selected user(s). If the first parameter is of
       the form `identifier%' identifier is matched against displays. Displays
       are named after the ttys they attach. The prefix `/dev/' or `/dev/tty'
       may be omitted from the identifier.  If identifier has a `#' or nothing
       appended it is matched against window numbers and titles. Omitting an
       identifier in front of the `#', `*' or `%'-character selects all users,
       displays or windows because a prefix-match is performed. Note that on
       the affected display(s) a short message will describe what happened.
       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
       windows (like "other") may be called again. In shared windows the
       command will be repeated for each attached display. Beware, when
       issuing toggle commands like "login"!  Some commands (e.g. "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
       background color.

       Examples:

              attrcolor b "R"

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

              attrcolor u "-u b"

       Use blue text instead of underline.

              attrcolor b ".I"

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

              attrcolor i "+b"

       Make bright colored text also bold.

       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
       command.  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
       specified number of seconds. Only the last line of output is used for
       substitution.
       If both the lifespan and the autorefresh parameters are zero, the
       backtick 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
       characters cleared by an erase/insert/scroll/clear operation will be
       displayed in the current background color. Otherwise the default
       background 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
       termcap (usually an audible bell).  The default message is

                   'Bell in window %n'

       An empty message can be supplied to the "bell_msg" command to suppress
       output of a message line (bell_msg "").  Without 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
       single character, a two-character sequence of the form "^x" (meaning
       "C-x"), a backslash followed by an octal number (specifying the ASCII
       code of the character), or a backslash followed by a second character,
       such as "\^" or "\\".  The argument can also be quoted, if you like.
       If no further argument is given, any previously established binding for
       this key is removed.  The command argument can be any command 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
       available 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
       superuser shell and a scrollback buffer of 1000 lines.

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

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

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

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

       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
       contain actions programmed by the user, one for the default actions
       used for terminal emulation and one for screen's copy mode to do cursor
       movement. See 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
       keyboard capability name (selectable with the -k option).
       Some keys on a VT100 terminal can send a different string if
       application mode is turned on (e.g the cursor keys).  Such keys have
       two entries in the translation table. You can select the application
       mode entry by specifying the -a option.
       The -t option tells screen not to do inter-character timing. One cannot
       turn off the timing if a termcap capability is used.
       Cmd can be any of screen's commands with an arbitrary number of args.
       If cmd is omitted the key-binding is removed from the table.
       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
       indicate that the corresponding charset/mapping should not be changed
       (set is padded to six characters internally by appending '.'  chars).
       New windows have "BBBB02" as default charset, unless a "encoding"
       command is active.
       The current setting can be viewed with the "info" command.

       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
       commands 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
       current 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
           columns 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
           newline 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
           contents 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
       differs 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
       windows 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
       session "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
       windows 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
       character is '^E' (octal 005) instead of '%'.  This was done to make a
       misinterpretation of program generated hardstatus lines impossible.  If
       the parameter status is omitted, the current default string is
       displayed.  Per default the hardstatus line of new windows is empty.

       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
       terminal.

       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
       windows is changed. This is initialized with `on' as distributed (see
       config.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
       displays 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
       dependency 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
       windows 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
       windows is changed. Initially line-wrap is on and can be toggled with
       the "wrap" command ("C-a r") or by means of "C-a : wrap on|off".

       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
       example 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
       currently 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
       converter 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 /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
       terminal 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
       window.

       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
       followed by an octal number (specifying the ASCII code of the
       character), or a backslash followed by a second character, such as "\^"
       or "\\".  The default is "^Aa".

       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
       (window) 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' output (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
       currently 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
       illustration of all 21 possible combinations. Each drawing shows the
       digits 2,1,0 representing the three file descriptors of newcommand. The
       box marked `W' is 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
       omitted. 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
       subcommand 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
       character 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
       hardstatus line. The first form toggles whether screen will use the
       hardware status line to display messages. If the flag is set to `off',
       these messages are overlaid in reverse video mode at the display line.
       The default setting is `on'.

       The second form tells screen what to do if the terminal doesn't have a
       hardstatus line (i.e. the termcap/terminfo capabilities "hs", "ts",
       "fs" and "ds" are not set). If the type "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
       supports 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
       window (settable via "ESC]0;<string>^G" or "ESC_<string>ESC\") is
       displayed.  You can customize this to any string you like including the
       escapes from the "STRING ESCAPES" chapter. If you leave out the
       argument string, the current string is displayed.

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

       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
       specify 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
       followed 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
       command 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
       inactivity 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
       CONTROL):

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

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

       The currently active character set (G0, G1, G2, or G3) and in square
       brackets the terminal character sets that are currently designated as
       G0 through G3 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
       processes in the windows may continue, as the windows are in the
       `detached' state. The screenlock program may be changed through the
       environment variable $LOCKPRG (which must be set in the shell from
       which screen is started) and is executed with the user's uid and gid.
       Warning: When you leave other shells unlocked and 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
       continues and more than another two minutes have passed, a second time-
       stamp is added to document the restart of the output. You can change
       this timeout with the second form of the command. The third form is
       used for customizing the time-stamp string (`-- %n:%t -- time-stamp --
       %M/%d/%y %c:%s --\n' by default).

       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
       example, multiple keys can be assigned to one function in a single
       statement.

       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
       windows.

       msgminwait sec

       Defines the time screen delays a new message when one message is
       currently 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
       familiar with the game "nethack", you may enjoy the nethack-style
       messages which will often blur the facts a little, but are much funnier
       to read. Anyway, standard messages often tend to be unclear as well.
       This option is only available if screen was compiled with the NETHACK
       flag defined. 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
       connection gets cut but no hangup is received. If nonblock is off (this
       is the default) screen waits until the display restarts to accept the
       output. If nonblock is on, screen waits until the timeout is reached
       (on is treated as 1s). If the display still doesn't receive characters,
       screen will consider it "blocked" and stop sending characters to it. If
       at some time it restarts to accept characters, screen will unblock the
       display and redisplay the updated window contents.

       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
       masquerading as your uid (i.e. any superuser.)  If no crypted password
       is specified, screen prompts twice for typing a password and places its
       encryption 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
       single 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
       signal 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
       performed. 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
       capabilities "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
       terminals the keys C-4 and C-\ are identical.  This makes the default
       bindings 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
       "bufferfile" 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
       register specified or entered at the prompt. With two arguments it
       reads the contents of the named file into the register, just as readbuf
       reads the screen-exchange file into the paste buffer.  You can tell
       screen the encoding of the file via the -e option.  The following
       example will paste the system's password file into the screen window
       (using register p, where a copy remains):

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

       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"
       command.

       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
       command is specified after "screen", this command (with the given
       arguments) 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
       additional 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
       "defscrollback" 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
       parameter 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
       omitted, the name of this session is displayed. Caution: The $STY
       environment variables still reflects the old name. This may result in
       confusion.  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
       specified, the user will be prompted to enter a value.  If no
       parameters are specified, the user will be prompted for both variable
       and value. The environment is inherited by all subsequently forked
       shells.

       setsid [on|off]

       Normally screen uses different sessions and process groups for the
       windows. 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
       specified 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
       entitled "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
       seconds.  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
       milliseconds 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
       command file before screen's current directory.

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

       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
       modifiers.  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
       displayed 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
       cannot 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
       parameters 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
       windows.  You have to place these commands in one of the screenrc
       startup files, as they are meaningless once the terminal emulator is
       booted.
       If your system 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
       interpolation (using `%') is required. Note that termcap names of the
       capabilities have to be used with the `terminfo' command.
       In many cases, where the arguments are valid in both terminfo and
       termcap syntax, you can use the command `termcapinfo', which is just a
       shorthand for a pair of `termcap' and `terminfo' commands with
       identical arguments.

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

       Each tweak argument contains one or more termcap defines (separated by
       `:'s) to be inserted at the start of the appropriate termcap entry,
       enhancing it or overriding existing values.  The first tweak modifies
       your terminal's termcap, and contains definitions that your terminal
       uses to perform certain functions.  Specify a null string to leave this
       unchanged (e.g. '').  The second (optional) tweak modifies all the
       window termcaps, and should contain definitions that screen understands
       (see 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
       specified, screen prompts for one. This command was known as `aka' in
       previous 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.
       Omitting the parameter toggles the setting. If a second parameter is
       given, the display's encoding is also changed (this should rather be
       done with screen's "-U" option).  See also "defutf8", which changes the
       default setting of a new window.

       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
       window 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
       terminal'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
       window 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
       occupied 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
       column of a line will wrap to the start of the following line.  As an
       added feature, backspace (^H) will also wrap through the left margin to
       the previous line.  Default is `on'.

       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.
       Calling zombie without parameters will clear the zombie setting, thus
       making 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
       message 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
       termcap, 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
       terminals 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
       "CUSTOMIZATION"). 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
          specified as the first parameter, then the window is directly
          connected to this device.  This window type is similar to "screen cu
          -l /dev/ttya".  Read and write access is required on the device
          node, an exclusive open is attempted on the node to mark the
          connection line as busy.  An optional parameter is allowed
          consisting of a comma separated list of flags in the notation used
          by stty(1):

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

          cs8 or cs7
                 Specify the transmission of eight (or seven) bits per byte.

          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
          parameter 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
          TIOCSOFTCAR bit is set, the signals `CTS' or `CD' are shown in
          parenthesis, respectively.

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

       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
          connection in square brackets ([ and ]) at the end of the status
          line.

          b      BINARY. The connection is in binary mode.

          e      ECHO. Local echo is disabled.

          c      SGA. The connection is in `character mode' (default: `line
                 mode').

          t      TTYPE. The terminal type has been requested by the remote
                 host.  Screen sends the name "screen" unless instructed
                 otherwise (see also the command `term').

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

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

          Additional flags for debugging are x, t and n (XDISPLOC, TSPEED and
          NEWENV).

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

          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
       current 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
              relative to the right margin by using '-'. The padding truncates
              the string if the specified position lies before the current
              position. 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
       understand 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
       description]". The attribute modifier must be prefixed by a change type
       indicator 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
       specifying 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
       background 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
              background.

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

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

       Each window has an initial flow-control value set with either the -f
       option or the "defflow" .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
       "interrupt" option (add the "interrupt" flag to the "flow" command in
       your .screenrc, or use the -i command-line option).  This causes the
       output that screen has accumulated from the interrupted program to be
       flushed.  One disadvantage is that the virtual terminal's memory
       contains the non-flushed version of the output, which in rare cases can
       cause minor inaccuracies in the output.  For example, if you switch
       screens and return, or update the screen with "C-a l" you would see the
       version of the output you would have gotten without "interrupt" being
       on.  Also, you might need to turn off flow-control (or use auto-flow
       mode to turn it off automatically) when running a program that expects
       you to type the interrupt character as input, as it is possible to
       interrupt the output of the virtual terminal to your physical terminal
       when flow-control 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
       commands.  Normally the name displayed is the actual command name of
       the program created in the window.  However, it is sometimes useful to
       distinguish various programs of the same name or to change the name on-
       the-fly to reflect the current state of the window.

       The default name for all shell windows can be set with the "shelltitle"
       command 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
       setting 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
       portion 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
       specified 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
       previously 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-
       control 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
       characters 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
       terminal 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
       emulation may not be complete. In these cases screen has to tell the
       applications that some of the features are missing. This is no problem
       on machines using termcap, because screen can use the $TERMCAP variable
       to customize the standard screen termcap.

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

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

       The idea is that if you have a terminal which doesn't support an
       important feature (e.g. delete char or clear to EOS) you can build a
       new termcap/terminfo entry for screen (named "screen.<dumbterm>") in
       which this capability has been disabled. If this entry is installed on
       your machines you are able to do a rlogin and still keep the correct
       termcap/terminfo entry.  The terminal name is put in the $TERM variable
       of all new windows.  Screen also sets the $TERMCAP variable reflecting
       the capabilities of the virtual terminal emulated. Notice that,
       however, on machines using the terminfo database this variable has no
       effect.  Furthermore, the variable $WINDOW is set to the window number
       of each window.

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

       Also, you can customize the $TERMCAP value used by screen by using the
       "termcap" .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
       supported: lock shift G0 (SI), lock shift G1 (SO), lock shift G2, lock
       shift G3, single shift G2, and single shift G3.  When a virtual
       terminal is created or reset, the ASCII character set is designated as
       G0 through G3.  When the `G0' capability is present, screen evaluates
       the capabilities `S0', `E0', and `C0' if present. `S0' is the sequence
       the terminal uses to enable and start the graphics character set rather
       than SI.  `E0' is the corresponding replacement for SO. `C0' gives a
       character by character translation string that is used during semi-
       graphics mode. This string is built like the `acsc' terminfo
       capability.

       When the `po' and `pf' capabilities are present in the terminal's
       termcap entry, applications running in a screen window can send output
       to the printer port of the terminal.  This allows a user to have an
       application in one window sending output to a printer connected to the
       terminal, while all other windows are still active (the printer port is
       enabled and disabled again for each chunk of output).  As a side-
       effect, programs running in different windows can send output to the
       printer simultaneously.  Data sent to the printer is not displayed in
       the window.  The info command displays a line starting `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
       window'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
       virtual terminal if they can be efficiently implemented by the physical
       terminal.  For instance, `dl' (delete line) is only put into the
       $TERMCAP variable if the terminal supports either delete line itself or
       scrolling regions. Note that this may provoke confusion, when the
       session is reattached on a different terminal, as the value of $TERMCAP
       cannot be modified by parent processes.

       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
       functions, respectively.

       ESC E                      Next Line

       ESC D                      Index

       ESC M                      Reverse Index

       ESC H                      Horizontal Tab Set

       ESC Z                      Send VT100 Identification String

       ESC 7                 (V)  Save Cursor and Attributes

       ESC 8                 (V)  Restore Cursor and Attributes

       ESC [s                (A)  Save Cursor and Attributes

       ESC [u                (A)  Restore Cursor and Attributes

       ESC c                      Reset to Initial State

       ESC g                      Visual Bell

       ESC Pn p                   Cursor Visibility (97801)

           Pn = 6                 Invisible

                7                 Visible

       ESC =                 (V)  Application Keypad Mode

       ESC >                 (V)  Numeric Keypad Mode

       ESC # 8               (V)  Fill Screen with E's

       ESC \                 (A)  String Terminator

       ESC ^                 (A)  Privacy Message String (Message Line)

       ESC !                      Global Message String (Message Line)

       ESC k                      A.k.a. Definition String

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

       ESC _                 (A)  Application Program Command (Hardstatus)

       ESC ] 0 ; string ^G   (A)  Operating System Command (Hardstatus, xterm
                                  title hack)

       ESC ] 83 ; cmd ^G     (A)  Execute screen command. This only works if
                                  multi-user support is compiled into screen.
                                  The pseudo-user ":window:" is used to check
                                  the access control list. Use "addacl
                                  :window: -rwx #?" to create a user with no
                                  rights and allow only the needed commands.

       Control-N             (A)  Lock Shift G1 (SO)

       Control-O             (A)  Lock Shift G0 (SI)

       ESC n                 (A)  Lock Shift G2

       ESC o                 (A)  Lock Shift G3

       ESC N                 (A)  Single Shift G2

       ESC O                 (A)  Single Shift G3

       ESC ( Pcs             (A)  Designate character set as G0

       ESC ) Pcs             (A)  Designate character set as G1

       ESC * Pcs             (A)  Designate character set as G2

       ESC + Pcs             (A)  Designate character set as G3

       ESC [ Pn ; Pn H            Direct Cursor Addressing

       ESC [ Pn ; Pn f            same as above

       ESC [ Pn J                 Erase in Display

             Pn = None or 0       From Cursor to End of Screen

                  1               From Beginning of Screen to Cursor

                  2               Entire Screen

       ESC [ Pn K                 Erase in Line

             Pn = None or 0       From Cursor to End of Line

                  1               From Beginning of Line to Cursor

                  2               Entire Line

       ESC [ Pn X                 Erase character

       ESC [ Pn A                 Cursor Up

       ESC [ Pn B                 Cursor Down

       ESC [ Pn C                 Cursor Right

       ESC [ Pn D                 Cursor Left

       ESC [ Pn E                 Cursor next line

       ESC [ Pn F                 Cursor previous line

       ESC [ Pn G                 Cursor horizontal position

       ESC [ Pn `                 same as above

       ESC [ Pn d                 Cursor vertical position

       ESC [ Ps ;...; Ps m        Select Graphic Rendition

             Ps = None or 0       Default Rendition

                  1               Bold

                  2          (A)  Faint

                  3          (A)  Standout Mode (ANSI: Italicized)

                  4               Underlined

                  5               Blinking

                  7               Negative Image

                  22         (A)  Normal Intensity

                  23         (A)  Standout Mode off (ANSI: Italicized off)

                  24         (A)  Not Underlined

                  25         (A)  Not Blinking

                  27         (A)  Positive Image

                  30         (A)  Foreground Black

                  31         (A)  Foreground Red

                  32         (A)  Foreground Green

                  33         (A)  Foreground Yellow

                  34         (A)  Foreground Blue

                  35         (A)  Foreground Magenta

                  36         (A)  Foreground Cyan

                  37         (A)  Foreground White

                  39         (A)  Foreground Default

                  40         (A)  Background Black

                  ...

                  49         (A)  Background Default

       ESC [ Pn g                 Tab Clear

             Pn = None or 0       Clear Tab at Current Position

                  3               Clear All Tabs

       ESC [ Pn ; Pn r       (V)  Set Scrolling Region

       ESC [ Pn I            (A)  Horizontal Tab

       ESC [ Pn Z            (A)  Backward Tab

       ESC [ Pn L            (A)  Insert Line

       ESC [ Pn M            (A)  Delete Line

       ESC [ Pn @            (A)  Insert Character

       ESC [ Pn P            (A)  Delete Character

       ESC [ Pn S                 Scroll Scrolling Region Up

       ESC [ Pn T                 Scroll Scrolling Region Down

       ESC [ Pn ^                 same as above

       ESC [ Ps ;...; Ps h        Set Mode

       ESC [ Ps ;...; Ps l        Reset Mode

             Ps = 4          (A)  Insert Mode

                  20         (A)  Automatic Linefeed Mode

                  34              Normal Cursor Visibility

                  ?1         (V)  Application Cursor Keys

                  ?3         (V)  Change Terminal Width to 132 columns

                  ?5         (V)  Reverse Video

                  ?6         (V)  Origin Mode

                  ?7         (V)  Wrap Mode

                  ?9              X10 mouse tracking

                  ?25        (V)  Visible Cursor

                  ?47             Alternate Screen (old xterm code)

                  ?1000      (V)  VT200 mouse tracking

                  ?1047           Alternate Screen (new xterm code)

                  ?1049           Alternate Screen (new xterm code)

       ESC [ 5 i             (A)  Start relay to printer (ANSI Media Copy)

       ESC [ 4 i             (A)  Stop relay to printer (ANSI Media Copy)

       ESC [ 8 ; Ph ; Pw t        Resize the window to `Ph' lines and `Pw'
                                  columns (SunView special)

       ESC [ c                    Send VT100 Identification String

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

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

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


SPECIAL TERMINAL CAPABILITIES

       The following table describes all terminal capabilities that are
       recognized 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'
                    command 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
                    section.

       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
       feature if you want to work with a common standard character set (say
       ISO8851-latin1) even on terminals that scatter the more unusual
       characters over several national language font pages.

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

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

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

       Here is an example:

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

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

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

       This example shows one use of the extension:

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

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


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
                                         initialization files.
       $SYSSCREENRC
       /etc/screenrc                     screen initialization commands
       $SCREENRC
       $HOME/.screenrc                   Read in after /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
                                         function
       /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
       /var/run/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
       MERCHANTABILITY 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
       Laumann.


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/utilities/screen. The subdirectory `private' contains the latest
       beta testing release. If you want to help, send a note to screen@uni-
       erlangen.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 "/var/run/utmp".

       o  Entries in "/var/run/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
          window 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)

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