Seth Woolley's Man Viewer

screen(1) - screen, screen - screen manager with VT100/ANSI terminal emulation - man 1 screen

([section] manual, -k keyword, -K [section] search, -f whatis)
man plain no title

SCREEN(1)                                                            SCREEN(1)



NAME
       screen - screen manager with VT100/ANSI terminal emulation



SYNOPSIS
       screen [ -options ] [ cmd [ args ] ]
       screen -r [[pid.]tty(1,4)[.host(1,5)]]
       screen -r sessionowner/[[pid.]tty(1,4)[.host(1,5)]]



DESCRIPTION
       Screen is a full-screen window manager that multiplexes a physical ter-
       minal between several processes (typically interactive  shells).   Each
       virtual(5,8) terminal provides the functions of a DEC VT100 terminal and, in(1,8)
       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(1,3,n,1 builtins)  buffer  for
       each virtual(5,8) 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(1,8)  it
       (or  the  specified  command) and then gets(3,n) out of your way so that you
       can use the program as you normally would.  Then, at any time(1,2,n), you  can
       create new (full-screen) windows with other programs in(1,8) them (including
       more shells), kill(1,2,1 builtins) existing windows, view a list of windows, turn  out-
       put  logging  on and off, copy-and-paste text between windows, view the
       scrollback history(1,3,n,1 builtins), switch(1,n) between windows in(1,8) whatever manner you wish,
       etc.  All  windows  run  their  programs completely independent of each
       other. Programs continue to run when their window is currently not vis-
       ible and even when the whole screen session is detached from the user's
       terminal.  When a program terminates, screen (per  default)  kills  the
       window  that  contained  it.  If this window was in(1,8) the foreground, the
       display switches to the previous  window;  if(3,n)  none  are  left,  screen
       exits.

       Everything  you type is sent to the program running in(1,8) the current win-
       dow.  The only exception to this is the one keystroke that is  used  to
       initiate  a  command  to  the window manager.  By default, each command
       begins with a control-a (abbreviated C-a from now on), and is  followed
       by one other keystroke.  The command character and all the key bindings
       can be fully customized to be anything you like, though they are always
       two characters in(1,8) 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(1,8) caret notation.

       The standard way to create a new window is to type "C-a c".  This  cre-
       ates  a  new window running a shell and switches to that window immedi-
       ately, regardless of the state of the process running  in(1,8)  the  current
       window.   Similarly,  you can create a new window with a custom command
       in(1,8) it by first binding the command to a keystroke  (in(1,8)  your  .screenrc
       file(1,n)  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(1,8) the $STY environ-
       ment variable) who will use it to create the  new  window.   The  above
       example would start the emacs editor (editing prog.c) and switch(1,n) to its
       window.

       If "/etc/utmp" is writable by screen, an  appropriate  record  will  be
       written  to  this  file(1,n) for each window, and removed when the window is
       terminated.  This is useful for working with "talk",  "script",  "shut-
       down(2,8)",  "rsend",  "sccs"  and  other similar programs that use the utmp
       file(1,n) to determine who you are. As long as screen is active on your ter-
       minal,  the  terminal's  own  record is removed from the utmp file. See
       also "C-a L".



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

       If  you're  impatient  and want to get started without doing a lot more
       reading, you should remember this one command:  "C-a ?".  Typing  these
       two characters will display a list of the available screen commands and
       their bindings. Each keystroke is discussed in(1,8) 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(1,3,5) of your terminal's termcap that has  automatic
       margins  turned off. This will ensure an accurate and optimal update(7,n) of
       the screen in(1,8) all circumstances. Most terminals nowadays  have  "magic(4,5)"
       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(1,8) 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(1,8) each win-
            dow's termcap, even if(3,n) screen must redraw parts of the display  in(1,8)
            order to implement a function.

       -A   Adapt  the  sizes of all windows to the size of the current termi-
            nal.  By default, screen tries to restore  its  old  window  sizes
            when  attaching  to  resizable  terminals  (those with "WS" in(1,8) its
            description, e.g. suncmd or some xterm).

       -c file(1,n)
            override the default configuration file(1,n) from "$HOME/.screenrc"  to
            file(1,n).

       -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(3,n) necessary detach it first.

       -d -R   Reattach a session and if(3,n) necessary detach or  even  create  it
               first.

       -d -RR  Reattach  a  session  and if(3,n) necessary detach or create it. Use
               the first session if(3,n) more than one session is available.

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

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

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

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

       -e xy
            specifies the command character to be x and the character generat-
            ing a literal command character to y (when typed after the command
            character).   The default is "C-a" and `a', which can be specified
            as "-e^Aa".  When creating a screen session, this option sets  the
            default  command character. In a multiuser session all users(1,5) 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(1,3,n,1 builtins) scrollback buffer to be num lines high.

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

       -l and -ln
            turns  login(1,3,5)  mode  on  or off (for /etc/utmp updating).  This can
            also be defined through the "deflogin" .screenrc command.

       -ls and -list
            does not start screen, but prints a list of  pid.tty.host  strings
            identifying  your screen sessions.  Sessions marked `detached' can
            be resumed with "screen -r". Those marked `attached'  are  running
            and  have a controlling terminal. If the session runs in(1,8) multiuser
            mode, it is  marked  `multi'.  Sessions  marked  as  `unreachable'
            either  live  on  a  different host(1,5) or are `dead'.  An unreachable
            session is considered dead, when its name matches either the  name
            of the local host(1,5), or the specified parameter, if(3,n) any.  See the -r
            flag for a description how to construct matches.  Sessions  marked
            as `dead' should be thoroughly checked and removed.  Ask your sys-
            tem administrator if(3,n) 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(1,8) connection with the `-d'
            option:

       -d -m   Start screen in(1,8) "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(1,8) "detached" mode, but doesn't fork  a
               new process. The command exits if(3,n) 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(7,n,1 builtins) in(1,8) your .screenrc by specifying `OP'
            in(1,8) 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(2,n) a command via the "-X" option
            to a specific window. As with screen's select(2,7,2 select_tut) commant, "-" selects
            the  blank  window.  As a special case for reattach, "=" brings up
            the windowlist on the blank window.

       -q   Suppress printing of error(8,n) messages. In combination with "-ls" the
            exit(3,n,1 builtins)  value  is  as  follows: 9 indicates a directory without ses-
            sions. 10 indicates a directory with running  but  not  attachable
            sessions.  11 (or more) indicates 1 (or more) usable sessions.  In
            combination with "-r" the exit(3,n,1 builtins) value is as follows:  10  indicates
            that  there  is  no session to resume. 12 (or more) indicates that
            there are 2 (or more) sessions to resume and  you  should  specify
            which one to choose.  In all other cases "-q" has no effect.

       -r [pid.tty.host]
       -r sessionowner/[pid.tty.host]
            resumes  a detached screen session.  No other options (except com-
            binations with -d/-D) may be specified, though an optional  prefix
            of  [pid.]tty.host  may  be needed to distinguish between multiple
            detached screen sessions.  The second form is used to  connect  to
            another  user's  screen session which runs in(1,8) multiuser mode. This
            indicates that screen should look(1,8,3 Search::Dict) for sessions in(1,8)  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(3,n) -R had not been specified. The option  is  set(7,n,1 builtins)
            by default if(3,n) screen is run as a login-shell (actually screen uses
            "-xRR" in(1,8) 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(1,8) the environment variable  $SHELL  (or  "/bin/sh"  if(3,n)  not
            defined).   This can also be defined through the "shell" .screenrc
            command.

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

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

       -U   Run screen in(1,8) UTF-8 mode. This option tells screen that your  ter-
            minal sends and understands UTF-8 encoded characters. It also sets
            the default encoding(3,n) for new windows to `utf8'.

       -v   Print version(1,3,5) number.

       -wipe [match]
            does the same as "screen  -ls",  but  removes  destroyed  sessions
            instead of marking them as `dead'.  An unreachable session is con-
            sidered dead, when its name matches either the name of  the  local
            host(1,5),  or the explicitly given parameter, if(3,n) 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(1,8,3 Search::Dict) only for attached
            or detached screen sessions. Note that this command  doesn't  work
            if(3,n) the session is password protected.



DEFAULT KEY BINDINGS
       As  mentioned,  each screen command consists of a "C-a" followed by one
       other character.  For your convenience, all commands that are bound  to
       lower-case  letters  are also bound to their control character counter-
       parts (with the exception of "C-a a"; see below), thus, "C-a c" as well
       as  "C-a  C-c"  can be used to create a window. See section "CUSTOMIZA-
       TION" for a description of the command.


       The following table shows the default key bindings:

       C-a '       (select(2,7,2 select_tut))      Prompt for a window name or number to  switch(1,n)
                                 to.

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

       C-a 0       (select(2,7,2 select_tut) 0)
        ...           ...
       C-a 9       (select(2,7,2 select_tut) 9)
       C-a -       (select(2,7,2 select_tut) -)    Switch to window number 0  -  9,  or  to  the
                                 blank window.

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

       C-a C-a     (other)       Toggle  to  the  window displayed previously.
                                 Note that this binding defaults to  the  com-
                                 mand  character  typed twice, unless overrid-
                                 den.  For instance, if(3,n)  you  use  the  option
                                 "-e]x", this command becomes "]]".

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

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

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

       C-a B       (pow_break)   Reopen the terminal line and send(2,n) a break.

       C-a c
       C-a C-c     (screen)      Create  a  new window with a shell and switch(1,n)
                                 to that window.

       C-a C       (clear(1,3x,3x clrtobot))       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(5,8).

       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(1,n) "hardcopy.n".

       C-a H       (log)         Begins/ends logging of the current window  to
                                 the file(1,n) "screenlog.n".

       C-a i
       C-a C-i     (info(1,5,n))        Show info(1,5,n) about this window.

       C-a k
       C-a C-k     (kill(1,2,1 builtins))        Destroy current window.

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

       C-a L       (login(1,3,5))       Toggle  this  windows  login(1,3,5)  slot. Available
                                 only if(3,n) screen is configured  to  update(7,n)  the
                                 utmp database.

       C-a m
       C-a C-m     (lastmsg)     Repeat the last message displayed in(1,8) the mes-
                                 sage line.

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

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

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

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

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

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

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

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

       C-a S       (split(1,n))       Split the current region into two new ones.

       C-a t
       C-a C-t     (time(1,2,n))        Show system information.

       C-a v       (version(1,3,5))     Display the version(1,3,5) 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(1,7,1 tput))       Reset  the virtual(5,8) 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(1,3) of the current window.

       C-a {
       C-a }       (history(1,3,n,1 builtins))     Copy and paste a previous (command) line.

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

       C-a <       (readbuf)     Reads the screen-exchange file(1,n) into the paste
                                 buffer.

       C-a =       (removebuf)   Removes the file(1,n) used by C-a < and C-a >.

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

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

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



CUSTOMIZATION
       The  "socket(2,7,n)  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(2,7,n) directory.  If
       screen  is  not  running setuid-root, the user can specify any mode 700
       directory in(1,8) the environment variable $SCREENDIR.

       When screen is invoked, it executes initialization  commands  from  the
       files  "/usr/local/etc/screenrc"  and  ".screenrc"  in(1,8)  the user's home
       directory. These are the "programmer's defaults" that can be overridden
       in(1,8) the following ways: for the global screenrc file(1,n) screen searches for
       the environment variable $SYSSCREENRC (this  override  feature  may  be
       disabled  at compile-time). The user specific screenrc file(1,n) is searched
       in(1,8) $SCREENRC, then $HOME/.screenrc.  The command line option  -c  takes
       precedence over the above user screenrc files.

       Commands  in(1,8)  these  files  are  used to set(7,n,1 builtins) options, bind(2,n,1 builtins) functions to
       keys, and to automatically establish one or more windows at the  begin-
       ning  of  your  screen session.  Commands are listed one per line, with
       empty lines being ignored.  A command's arguments are separated by tabs
       or  spaces,  and  may  be surrounded by single or double quotes.  A `#'
       turns the rest of the line into a comment, except in(1,8) quotes.   Unintel-
       ligible  lines are warned about and ignored.  Commands may contain ref-
       erences to environment variables. The syntax is the shell-like "$VAR  "
       or "${VAR}". Note that this causes incompatibility with previous screen
       versions, as now the '$'-character has to be protected with '\'  if(3,n)  no
       variable  substitution shall be performed. A string(3,n) in(1,8) single-quotes is
       also protected from variable substitution.

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

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

       The following commands are available:

       acladd usernames [crypted-pw]
       addacl usernames

       Enable users(1,5) to fully access(2,5) 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(2,5), use the
       `aclchg' command below.  If an optional second parameter  is  supplied,
       it  should  be  a crypted password for the named(5,8) user(s). `Addacl' is a
       synonym to `acladd'.  Multi user mode only.

       aclchg usernames permbits list
       chacl usernames permbits list

       Change permissions for a comma separated list of users. Permission bits
       are  represented  as `r', `w' and `x'. Prefixing `+' grants the permis-
       sion, `-' removes it. The third parameter is a comma separated list  of
       commands and/or windows (specified either by number or title). The spe-
       cial list `#' refers to all windows, `?' to all commands. if(3,n)  usernames
       consists  of a single `*', all known users(1,5) 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(7,n,1 builtins) and no other user obtains
       a writelock for this window.  Other bits  are  currently  ignored.   To
       withdraw  the writelock from another user in(1,8) window 2: `aclchg username
       -w+w 2'.  To allow read-only access(2,5) to the session: `aclchg username -w
       "#"'.  As soon as a user's name is known to screen he can attach to the
       session and (per default) has full permissions for all command and win-
       dows. Execution permission for the acl commands, `at' and others should
       also be removed or the user may be able  to  regain  write(1,2)  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(2,5) 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(1,5) that share common access(2,5) 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(3,n)  a user fails an access(2,5) 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(1,8) are listed.

       aclumask [[users(1,5)]+bits |[users(1,5)]-bits .... ]
       umask [[users(1,5)]+bits |[users(1,5)]-bits .... ]

       This specifies the access(2,5) other users(1,5) have to windows that will be cre-
       ated  by  the  caller  of the command.  Users may be no, one or a comma
       separated list of known usernames. If no users(1,5) are specified, a list of
       all  currently  known  users(1,5)  is  assumed.   Bits is any combination of
       access(2,5) control bits allowed defined with the "aclchg" command. The spe-
       cial  username  "?" predefines the access(2,5) that not yet known users(1,5) will
       be granted to any window initially.  The special username  "??"  prede-
       fines  the  access(2,5) that not yet known users(1,5) 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(1,8) a background window that is being moni-
       tored, screen displays a notification in(1,8) the message line.  The notifi-
       cation  message  can  be re-defined by means of the "activity" command.
       Each occurrence of `%' in(1,8) message is replaced by the number of the win-
       dow  in(1,8)  which  activity  has  occurred, and each occurrence of `^G' is
       replaced by the definition for bell in(1,8) your termcap (usually an audible
       bell).  The default message is

                   'Activity in(1,8) 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(7,n,1 builtins) 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(7,n,1 builtins)  to on, "alternate screen" support is enabled in(1,8) virtual(5,8) termi-
       nals, just like in(1,8) xterm.  Initial setting is `off'.

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

       Execute a command at other displays  or  windows  as  if(3,n)  it  had  been
       entered there.  "At" changes the context (the `current window' or `cur-
       rent display' setting) of the command. If the first parameter describes
       a  non-unique  context, the command will be executed multiple times. If
       the first parameter is of the form  `identifier*'  then  identifier  is
       matched against user names.  The command is executed once for each dis-
       play of the selected user(s). If the first parameter  is  of  the  form
       `identifier%'  identifier  is  matched  against  displays. Displays are
       named(5,8) after the ttys they attach. The prefix `/dev/' or `/dev/tty(1,4)'  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(1,8) front of the `#', `*' or `%'-character selects all users(1,5),
       displays or windows because a prefix-match is performed. Note  that  on
       the  affected  display(s)  a short message will describe what happened.
       Permission is checked for initiator of the "at" command,  not  for  the
       owners  of  the affected display(s).  Note that the '#' character works
       as a comment introducer when it is preceded by whitespace. This can  be
       escaped by prefixing a '\'.  Permission is checked for the initiator of
       the "at" command, not for the owners of the affected display(s).
       Caveat: When matching against windows, the command is executed at least
       once  per window. Commands that change the internal arrangement of win-
       dows (like "other") may be called again. In shared windows the  command
       will be repeated for each attached display. Beware, when issuing toggle
       commands like "login(1,3,5)"!  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(1,8)  use,  the specified
       attribute/color modifier is also applied. If no modifier is given,  the
       current one is deleted. See the "STRING ESCAPES" chapter for the syntax
       of the modifier. Screen understands two pseudo-attributes,  "i"  stands
       for  high-intensity  foreground  color and "I" for high-intensity back-
       ground color.

       Examples:

              attrcolor b "R"

       Change the color to bright red if(3,n) bold text is to be printed.

              attrcolor u "-u b"

       Use blue text instead of underline.

              attrcolor b ".I"

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

              attrcolor i "+b"

       Make bright colored text also bold.

       autodetach on|off

       Sets  whether screen will automatically detach upon hangup, which saves
       all your running programs until they are resumed with a screen -r  com-
       mand.   When  turned off, a hangup signal(2,7) will terminate screen and all
       the processes it contains. Autodetach is on by default.

       autonuke on|off

       Sets whether a clear(1,3x,3x clrtobot) 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(3,n) escape.  The
       specified  lifespan  is  the number of seconds the output is considered
       valid. After this time(1,2,n), the command is run  again  if(3,n)  a  corresponding
       string(3,n)  escape  is  encountered.  The autorefresh parameter triggers an
       automatic refresh for caption and hardstatus strings after  the  speci-
       fied  number  of seconds. Only the last line of output is used for sub-
       stitution.
       If both the lifespan and the autorefresh parameters are zero, the back-
       tick  program is expected to stay in(1,8) the background and generate output
       once in(1,8) a while.  In this case, the command is executed right away  and
       screen  stores  the  last  line  of  output. If a new line gets(3,n) 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(7,n,1 builtins) to on, all char-
       acters cleared by an erase/insert/scroll/clear(1,3x,3x clrtobot) operation will  be  dis-
       played  in(1,8)  the  current  background color. Otherwise the default back-
       ground color is used.

       bell_msg [message]

       When a bell character is sent to a background window, screen displays a
       notification  in(1,8) the message line.  The notification message can be re-
       defined by this command.  Each occurrence of `%' in(1,8) 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(1,8) your term-
       cap (usually an audible bell).  The default message is

                   'Bell in(1,8) 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(2,n,1 builtins) [-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(1,8) the  "DEFAULT  KEY
       BINDINGS"  section, e.g. the command to create a new window is bound to
       "C-c" and "c".  The "bind(2,n,1 builtins)" command can be  used  to  redefine  the  key
       bindings and to define new bindings.  The key argument is either a sin-
       gle character, a two-character sequence of the form "^x"  (meaning  "C-
       x"), a backslash followed by an octal number (specifying the ASCII code
       of the character), or a backslash followed by a second character,  such
       as  "\^" or "\\".  The argument can also be quoted, if(3,n) 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(1,8) 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(2,n,1 builtins) ' ' windows
                   bind(2,n,1 builtins) ^k
                   bind(2,n,1 builtins) k
                   bind(2,n,1 builtins) K kill(1,2,1 builtins)
                   bind(2,n,1 builtins) ^f screen telnet foobar
                   bind(2,n,1 builtins) \033 screen -ln -t root -h 1000 9 su

       would bind(2,n,1 builtins) the space key to the command that displays a list of windows
       (so that the command usually invoked by "C-a C-w" would also be  avail-
       able  as  "C-a  space").  The  next three lines remove the default kill(1,2,1 builtins)
       binding from "C-a C-k" and "C-a k".  "C-a K" is then bound to the  kill(1,2,1 builtins)
       command.  Then  it  binds  "C-f" to the command "create a window with a
       TELNET connection to foobar", and bind(2,n,1 builtins) "escape"  to  the  command  that
       creates an non-login window with a.k.a. "root" in(1,8) slot #9, with a supe-
       ruser shell and a scrollback buffer of 1000 lines.

                   bind(2,n,1 builtins) -c demo1 0 select(2,7,2 select_tut) 10
                   bind(2,n,1 builtins) -c demo1 1 select(2,7,2 select_tut) 11
                   bind(2,n,1 builtins) -c demo1 2 select(2,7,2 select_tut) 12
                   bindkey "^B" command -c demo1

       makes "C-b 0" select(2,7,2 select_tut) window 10, "C-b 1" window 11, etc.

                   bind(2,n,1 builtins) -c demo2 0 select(2,7,2 select_tut) 10
                   bind(2,n,1 builtins) -c demo2 1 select(2,7,2 select_tut) 11
                   bind(2,n,1 builtins) -c demo2 2 select(2,7,2 select_tut) 12
                   bind(2,n,1 builtins) - command -c demo2

       makes "C-a - 0" select(2,7,2 select_tut) window 10, "C-a - 1" window 11, etc.

       bindkey [-d] [-m] [-a] [[-k|-t] string(3,n) [cmd args]]

       This command manages screen's input translation tables. Every entry  in(1,8)
       one  of  the  tables tells screen how to react if(3,n) a certain sequence of
       characters is encountered. There are three tables: one that should con-
       tain  actions  programmed by the user, one for the default actions used
       for terminal emulation and one for screen's  copy  mode  to  do  cursor
       movement.  See  section  "INPUT  TRANSLATION" for a list of default key
       bindings.
       If the -d option is given,  bindkey  modifies  the  default  table,  -m
       changes  the  copy mode table and with neither option the user table is
       selected.  The argument string(3,n) is the sequence of characters  to  which
       an action is bound. This can either be a fixed string(3,n) or a termcap key-
       board capability name (selectable with the -k option).
       Some keys on a VT100 terminal can send(2,n) a different string(3,n)  if(3,n)  applica-
       tion  mode  is  turned  on  (e.g  the cursor keys).  Such keys have two
       entries in(1,8) the translation table. You can select(2,7,2 select_tut) 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(3,n) 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(2,7,2 select_tut) 1
       Make the "F1" key switch(1,n) to window one.

               bindkey -t foo stuff barfoo
       Make "foo" an abbreviation of the word "barfoo". Timeout is disabled so
       that users(1,5) 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(2,7) for duration*0.25 seconds to this window.  For non-
       Posix  systems  the  time(1,2,n)  interval  may be rounded up to full seconds.
       Most useful if(3,n) 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(2,7) 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(2,n,1 builtins) 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(3,n) no arguments
       are given.

       breaktype [tcsendbreak|TIOCSBRK |TCSBRK]

       Choose one of the available methods of generating a  break  signal(2,7)  for
       terminal  devices.  This command should affect the current window only.
       But it still behaves identical to "defbreaktype". This will be  changed
       in(1,8)  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(1,n) into the screen window
       (using the paste buffer, where a copy remains):

                   C-a : bufferfile /etc/passwd(1,5)
                   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(1,8) the c1 positions may want to turn this off.

       caption always|splitonly [string(3,n)]
       caption string(3,n) [string(3,n)]

       This  command  controls  the display of the window captions. Normally a
       caption is only used if(3,n) more than one window is shown  on  the  display
       (split(1,n)  screen  mode).  But if(3,n) the type is set(7,n,1 builtins) to always screen shows a
       caption even if(3,n) 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(3,n) as an additional argument.

       charset set(7,n,1 builtins)

       Change the current character set(7,n,1 builtins) slot designation and charset  mapping.
       The  first  four  character  of  set(7,n,1 builtins) are treated as charset designators
       while the fifth and sixth character must be in(1,8) range '0' to '3' and set(7,n,1 builtins)
       the GL/GR charset mapping. On every position a '.' may be used to indi-
       cate that the corresponding charset/mapping should not be changed  (set(7,n,1 builtins)
       is  padded  to  six characters internally by appending '.'  chars). New
       windows have "BBBB02" as default charset, unless a  "encoding(3,n)"  command
       is active.
       The current setting can be viewed with the "info(1,5,n)" command.

       chdir [directory]

       Change  the  current directory of screen to the specified directory or,
       if(3,n) 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(1,8)
       the  window.  You can use this command multiple times in(1,8) your .screenrc
       to start various windows in(1,8) different default directories, but the last
       chdir value will affect all the windows you create interactively.

       clear(1,3x,3x clrtobot)

       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(7,n,1 builtins)" keyword no longer  exists!  Usually  com-
       mands affect the current window rather than default settings for future
       windows. Change defaults with commands starting with 'def...'.

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

       command [-c class]

       This  command has the same effect as typing the screen escape character
       (^A). It is probably only useful for key bindings.  If the "-c"  option
       is  given,  select(2,7,2 select_tut)  the  specified  command class.  See also "bind(2,n,1 builtins)" and
       "bindkey".

       compacthist [on|off]

       This tells  screen  whether  to  suppress  trailing  blank  lines  when
       scrolling up text into the history(1,3,n,1 builtins) buffer.

       console(4,n) [on|off]

       Grabs  or un-grabs the machines console(4,n) output to a window.  Note: Only
       the owner of /dev/console(4,n) can grab the console(4,n) output.  This command is
       only available if(3,n) the machine supports the ioctl TIOCCONS.

       copy

       Enter  copy/scrollback mode. This allows you to copy text from the cur-
       rent window and its history(1,3,n,1 builtins) into the paste buffer. In this mode  a  vi-
       like `full screen editor' is active:
       Movement keys:
         h, j, k, l move(3x,7,3x curs_move) the cursor line by line or column by column.
         0,  ^  and  $  move(3x,7,3x curs_move) to the leftmost column, to the first or last non-
           whitespace character on the line.
         H, M and L move(3x,7,3x curs_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(3x,7,3x curs_move) the cursor word by word.
         B, E move(3x,7,3x curs_move) the cursor WORD by WORD (as in(1,8) 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(7,n,1 builtins) 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(1,8)  vi.   Vi
           does  not  allow one to yank rectangular blocks of text, but screen
           does. Press
         c or C to set(7,n,1 builtins) 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(1,8)  20  col-
           umns  left,  marks the beginning of the paste buffer, sets the left
           column, moves 5 columns down, sets the right column, and then marks
           the end of the paste buffer. Now try:
           "C-a [ M 20 l SPACE 10 l 5 j SPACE"

           and notice the difference in(1,8) the amount of text copied.
         J  joins lines. It toggles between 4 modes: lines separated by a new-
           line character (012), lines glued seamless, lines  separated  by  a
           single  whitespace  and  comma  separated  lines. Note that you can
           prepend the newline character with a carriage return character,  by
           issuing a "crlf on".
         v  is  for all the vi users(1,5) with ":set numbers" - it toggles the left
           margin between column 9 and 1. Press
         a before the final space key to toggle in(1,8) append mode. Thus the  con-
           tents  of the paste buffer will not be overwritten, but is appended
           to.
         A toggles in(1,8) append mode and sets a (second) mark.
         > sets the (second) mark and writes the contents of the paste  buffer
           to the screen-exchange file(1,n) (/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(3,n,1 builtins) copy mode.
         All keys not described here exit(3,n,1 builtins) 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(7,n,1 builtins)  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(3,n) 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(2,7)  for
       terminal  devices.  The preferred methods are tcsendbreak and TIOCSBRK.
       The third, TCSBRK, blocks the complete screen session for the  duration
       of  the  break,  but  it  may  be the only way to generate long breaks.
       Tcsendbreak and TIOCSBRK may or may not produce long breaks with spikes
       (e.g.  4 per second). This is not only system dependant, this also dif-
       fers between serial board  drivers.   Calling  "defbreaktype"  with  no
       parameter displays the current setting.

       defcharset [set(7,n,1 builtins)]

       Like  the  charset command except that the default setting for new win-
       dows is changed. Shows current default if(3,n) called without argument.

       defescape xy

       Set the default command characters. This is equivalent to the  "escape"
       except  that  it is useful multiuser sessions only. In a multiuser ses-
       sion "escape" changes the command character of the calling user,  where
       "defescape"  changes the default command characters for users(1,5) that will
       be added later.

       defflow on|off|auto(5,8) [interrupt]

       Same as the flow command except that the default setting for  new  win-
       dows  is  changed. Initial setting is `auto(5,8)'.  Specifying "defflow auto(5,8)
       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(7,n,1 builtins) 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(1,8) the window messages, but the directive escape  charac-
       ter is '^E' (octal 005) instead of '%'.  This was done to make a misin-
       terpretation of program generated hardstatus lines impossible.  If  the
       parameter  status  is omitted, the current default string(3,n) is displayed.
       Per default the hardstatus line of new windows is empty.

       defencoding enc

       Same as the encoding(3,n) command except that the default  setting  for  new
       windows is changed. Initial setting is the encoding(3,n) taken from the ter-
       minal.

       deflog on|off

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

       deflogin on|off

       Same  as the login(1,3,5) command except that the default setting for new win-
       dows is changed. This is initialized with `on' as distributed (see con-
       fig.h.in).

       defmode mode

       The mode of each newly allocated pseudo-tty is set(7,n,1 builtins) to mode.  Mode is an
       octal number.  When no "defmode" command is given, mode 0622 is used.

       defmonitor on|off

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

       defnonblock on|off|numsecs

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

       defobuflimit limit

       Same as the obuflimit command except that the default setting  for  new
       displays  is  changed. Initial setting is 256 bytes.  Note that you can
       use the special 'OL' terminal capability if(3,n) you want to have  a  depen-
       dency on the terminal type.

       defscrollback num

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

       defshell command

       Synonym to the shell command. See there.

       defsilence on|off

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

       defslowpaste msec"

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

       defutf8 on|off

       Same as the utf8 command except that the default setting for  new  win-
       dows  is  changed.  Initial  setting is `on' if(3,n) screen was started with
       "-U", otherwise `off'.

       defwrap on|off

       Same as the wrap command except that the default setting for  new  win-
       dows  is changed. Initially line-wrap is on and can be toggled with the
       "wrap" command ("C-a r") or by means of "C-a : wrap on|off".

       defwritelock on|off|auto(5,8)

       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(2,7,n)  the  connection  to  the  terminal
       ("hangup").

       dinfo

       Show what screen thinks about your terminal. Useful if(3,n) 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(1,8) a builtin  table  and  the  resulting
       character  is  inserted  in(1,8)  the input stream. For example, if(3,n) the user
       enters 'a"', an a-umlaut will  be  inserted.  If  the  first  character
       entered  is  a 0 (zero), screen will treat the following characters (up
       to three) as an octal number instead.  The optional argument preset  is
       treated  as user input, thus one can create an "umlaut" key.  For exam-
       ple the command "bindkey ^K digraph '"'" enables the user  to  generate
       an a-umlaut by typing CTRL-K a.

       dumptermcap

       Write the termcap entry for the virtual(5,8) terminal optimized for the cur-
       rently  active  window  to  the   file(1,n)   ".termcap"   in(1,8)   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(7,n,1 builtins) up by screen for
       each window. For terminfo based systems you will need  to  run  a  con-
       verter like captoinfo and then compile the entry with tic.

       echo(1,3x,1 builtins) [-n] message

       The  echo(1,3x,1 builtins)  command may be used to annoy screen users(1,5) with a 'message of
       the day'. Typically installed in(1,8)  a  global  /local/etc/screenrc.   The
       option  "-n"  may be used to suppress the line feed.  See also "sleep(1,3)".
       Echo is also useful for online checking of environment variables.

       encoding(3,n) enc [enc]

       Tell screen how to interpret the input/output. The first argument  sets
       the encoding(3,n) of the current window. Each window can emulate a different
       encoding. The optional second parameter overwrites the encoding(3,n) of  the
       connected terminal. It should never be needed as screen uses the locale(3,5,7)
       setting to detect the encoding.  There is also a way to select(2,7,2 select_tut) a termi-
       nal  encoding(3,n)  depending on the terminal type by using the "KJ" termcap
       entry.

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

       See also "defencoding", which changes the default setting of a new win-
       dow.

       escape xy

       Set  the  command character to x and the character generating a literal
       command character (by triggering the "meta" command) to y  (similar  to
       the  -e  option).   Each  argument is either a single character, a two-
       character sequence of the form "^x" (meaning "C-x"), a  backslash  fol-
       lowed  by an octal number (specifying the ASCII code of the character),
       or a backslash followed by a second character, such as  "\^"  or  "\\".
       The default is "^Aa".

       eval command1 [command2 ...]

       Parses and executes each argument as separate command.

       exec(3,n,1 builtins) [[fdpat] newcommand [args ...]]

       Run  a  unix subprocess (specified by an executable path newcommand and
       its optional arguments) in(1,8) the current window. The flow of data between
       newcommands  stdin/stdout/stderr, the process originally started in(1,8) the
       window (let us call it "application-process") and screen  itself  (win-
       dow)  is  controlled by the filedescriptor pattern fdpat.  This pattern
       is basically a three character sequence representing stdin, stdout  and
       stderr of newcommand. A dot (.) connects the file(1,n) descriptor to screen.
       An exclamation mark (!) causes the file(1,n) descriptor to be  connected  to
       the application-process. A colon (:) combines both.  User input will go
       to newcommand unless newcommand receives the application-process'  out-
       put  (fdpats  first  character  is  `!' or `:') or a pipe(2,8) symbol (|) is
       added (as a fourth character) to the end of fdpat.
       Invoking `exec(3,n,1 builtins)' without arguments shows name and arguments of the  cur-
       rently  running  subprocess  in(1,8) this window. Only one subprocess a time(1,2,n)
       can be running in(1,8) each window.
       When a subprocess is running the `kill(1,2,1 builtins)' command will affect it  instead
       of the windows process.
       Refer  to  the postscript file(1,n) `doc/fdpat.ps' for a confusing illustra-
       tion of all 21 possible combinations. Each  drawing  shows  the  digits
       2,1,0  representing  the  three file(1,n) 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(5,8) side.

       Abbreviations:
       Whitespace between the word `exec(3,n,1 builtins)' and fdpat and  the  command  can  be
       omitted. Trailing dots and a fdpat consisting only of dots can be omit-
       ted. A simple `|' is synonymous for the pattern `!..|'; the  word  exec(3,n,1 builtins)
       can be omitted here and can always be replaced by `!'.

       Examples:

              exec(3,n,1 builtins) ... /bin/sh
              exec(3,n,1 builtins) /bin/sh
              !/bin/sh

       Creates  another  shell in(1,8) 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(3,n,1 builtins) !.. stty 19200
              exec(3,n,1 builtins) ! stty 19200
              !!stty 19200

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

              exec(3,n,1 builtins) !..| less(1,3)
              |less(1,3)

       This adds a pager to the window output. The special  character  `|'  is
       needed  to  give  the  user control over the pager although it gets(3,n) its
       input from the window's process. This works, because  less(1,3)  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(1,8) window x" messages, whenever
       the string(3,n) "Error" appears in(1,8) 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(3,n)
       the window is displayed more than once.

       flow [on|off|auto(5,8)]

       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(1,8)  this
       document  for  full details and note, that this is subject to change in(1,8)
       future releases.  Default is set(7,n,1 builtins) by `defflow'.

       focus [up|down|top|bottom]

       Move the input focus to the next region. This is done in(1,8) a  cyclic  way
       so  that the top region is selected after the bottom one. If no subcom-
       mand is given it defaults to `down'. `up' cycles in(1,8) the opposite order,
       `top' and `bottom' go to the top and bottom region respectively. Useful
       bindings are (j and k as in(1,8) vi)
           bind(2,n,1 builtins) j focus down
           bind(2,n,1 builtins) k focus up
           bind(2,n,1 builtins) t focus top
           bind(2,n,1 builtins) b focus bottom

       gr [on|off]

       Turn GR charset switching on/off. Whenever screen sees an input charac-
       ter with the 8th bit set(7,n,1 builtins), it will use the charset stored in(1,8) 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(1,n)]

       Writes out the currently displayed image to the file(1,n) file(1,n),  or,  if(3,n)  no
       filename  is specified, to hardcopy.n in(1,8) the default directory, where n
       is the number of the current window.  This either appends or overwrites
       the  file(1,n) if(3,n) it exists. See below.  If the option -h is specified, dump
       also the contents of the scrollback buffer.

       hardcopy_append on|off

       If set(7,n,1 builtins) 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(1,8) screen's current working directory.

       hardstatus [on|off]
       hardstatus [always]lastline|message|ignore [string(3,n)]
       hardstatus string(3,n) [string(3,n)]

       This  command  configures the use and emulation of the terminal's hard-
       status line. The first form toggles whether screen will use  the  hard-
       ware  status  line  to  display  messages. If the flag is set(7,n,1 builtins) to `off',
       these messages are overlaid in(1,8) reverse video mode at the display  line.
       The default setting is `on'.

       The  second form tells screen what to do if(3,n) the terminal doesn't have a
       hardstatus line (i.e. the  termcap/terminfo  capabilities  "hs",  "ts",
       "fs" and "ds" are not set(7,n,1 builtins)). 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(3,n) the terminal sup-
       ports a hardstatus.

       The third form specifies the contents of the hardstatus line.  '%h'  is
       used  as default string(3,n), i.e. the stored hardstatus of the current win-
       dow (settable via "ESC]0;<string(3,n)>^G"  or  "ESC_<string(3,n)>ESC\")  is  dis-
       played.   You  can  customize this to any string(3,n) you like including the
       escapes from the "STRING ESCAPES" chapter. If you leave out  the  argu-
       ment string(3,n), the current string(3,n) is displayed.

       You  can mix the second and third form by providing the string(3,n) as addi-
       tional argument.

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

       Set the display height to a specified number of lines. When no argument
       is given it toggles between 24 and 42 lines display. You can also spec-
       ify a width if(3,n) you want to change both values.   The  -w  option  tells
       screen  to  leave  the  display  size unchanged and just set(7,n,1 builtins) the window
       size, -d vice versa.

       help [-c class]

       Not really a online help, but displays a help screen  showing  you  all
       the  key bindings.  The first pages list all the internal commands fol-
       lowed by their current bindings.  Subsequent  pages  will  display  the
       custom  commands,  one  command  per key.  Press space when you're done
       reading each page, or return to exit(3,n,1 builtins) 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(1,3,n,1 builtins)

       Usually  users(1,5)  work  with  a shell that allows easy access(2,5) to previous
       commands.  For example csh has the command "!!" to repeat the last com-
       mand executed.  Screen allows you to have a primitive way of re-calling
       "the command that started ...": You just type the first letter of  that
       command, then hit `C-a {' and screen tries to find a previous line that
       matches with the `prompt character' to the left  of  the  cursor.  This
       line  is  pasted into this window's input queue.  Thus you have a crude
       command history(1,3,n,1 builtins) (made up by  the  visible  window  and  its  scrollback
       buffer).

       hstatus status

       Change the window's hardstatus line to the string(3,n) status.

       idle [timeout(1,3x,3x cbreak) [cmd args]]

       Sets  a command that is run after the specified number of seconds inac-
       tivity is reached. This command will normally be the "blanker"  command
       to  create  a  screen blanker, but it can be any screen command.  If no
       command is specified, only the timeout(1,3x,3x cbreak) is set. A timeout(1,3x,3x cbreak)  of  zero  (ot
       the  special  timeout(1,3x,3x cbreak)  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(1,8)  searches.  Default  is
       `off'.

       info(1,5,n)

       Uses  the  message  line  to display some information about the current
       window: the cursor position in(1,8) the form  "(column,row)"  starting  with
       "(1,1)",  the terminal width and height plus the size of the scrollback
       buffer in(1,8) lines, like in(1,8) "(80,24)+50",  the  current  state  of  window
       XON/XOFF  flow  control  is shown like this (See also section FLOW CON-
       TROL):

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

       The current line wrap setting (`+wrap' indicates enabled, `-wrap'  not)
       is  also  shown. The flags `ins', `org', `app', `log', `mon' or `nored'
       are displayed when the window is in(1,8) insert mode, origin mode,  applica-
       tion-keypad  mode,  has  output logging, activity monitoring or partial
       redraw enabled.

       The currently active character set(7,n,1 builtins) (G0, G1, G2, or G3)  and  in(1,8)  square
       brackets  the  terminal character sets that are currently designated as
       G0 through G3 is shown. If the window is  in(1,8)  UTF-8  mode,  the  string(3,n)
       "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(1,8)  a  non-default
       state,  the  info(1,5,n) line is started with a string(3,n) identifying the current
       state.
       For system information use the "time(1,2,n)" command.

       ins_reg [key]

       No longer exists, use "paste" instead.

       kill(1,2,1 builtins)

       Kill current window.
       If there is an `exec(3,n,1 builtins)' command running then it is killed. Otherwise  the
       process  (shell) running in(1,8) 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(1,2,1 builtins) screen switches to the previously displayed window.
       Note: Emacs users(1,5) should keep this command  in(1,8)  mind,  when  killing  a
       line.   It  is recommended not to use "C-a" as the screen escape key or
       to rebind kill(1,2,1 builtins) to "C-a K".

       lastmsg

       Redisplay the last contents of  the  message/status  line.   Useful  if(3,n)
       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(3,n) no other is available). Screen  does  not
       accept(2,8)  any  command keys until this program terminates. Meanwhile pro-
       cesses in(1,8)  the  windows  may  continue,  as  the  windows  are  in(1,8)  the
       `detached'  state.  The  screenlock  program may be changed through the
       environment variable $LOCKPRG (which must be  set(7,n,1 builtins)  in(1,8)  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(7,n,1 builtins) 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(1,n) "screenlog.n"
       in(1,8) 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(1,n) if(3,n) it already exists. The
       current contents and the contents of the  scrollback  history(1,3,n,1 builtins)  are  not
       included in(1,8) the session log.  Default is `off'.

       logfile filename
       logfile flush(8,n) 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(1,3,5) [on|off]

       Adds or removes the entry in(1,8) the utmp database  file(1,n)  for  the  current
       window.  This controls if(3,n) the window is `logged in(1,8)'.  When no parameter
       is given, the login(1,3,5) state of the window is  toggled.   Additionally  to
       that  toggle,  it  is convenient having a `log in(1,8)' and a `log out' key.
       E.g. `bind(2,n,1 builtins) I login(1,3,5) on' and `bind(2,n,1 builtins) O login(1,3,5) off' will map these keys to be
       C-a  I  and C-a O.  The default setting (in(1,8) config.h.in) should be "on"
       for a screen that runs under suid-root.  Use the "deflogin" command  to
       change  the default login(1,3,5) 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(3,n) [string(3,n)]

       This command controls logfile time-stamp mechanism of screen.  If time-
       stamps  are  turned  "on",  screen adds a string(3,n) containing the current
       time(1,2,n) to the logfile after two minutes of inactivity.  When output  con-
       tinues  and  more  than another two minutes have passed, a second time-
       stamp is added to document the restart of the output.  You  can  change
       this  timeout(1,3x,3x cbreak)  with  the  second form of the command. The third form is
       used for customizing the time-stamp string(3,n) (`-- %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(1,8)
       the default bindkey table. See also "bindkey".

       mapnotnext

       Like mapdefault, but don't even look(1,8,3 Search::Dict) in(1,8) the default bindkey table.

       maptimeout [timo]

       Set the inter-character timer for input sequence detection to a timeout(1,3x,3x cbreak)
       of  timo ms. The default timeout(1,3x,3x cbreak) is 300ms. Maptimeout with no arguments
       shows the current setting.  See also "bindkey".

       markkeys string(3,n)

       This is a method of changing the keymap  used  for  copy/history(1,3,n,1 builtins)  mode.
       The  string(3,n)  is made up of oldchar=newchar pairs which are separated by
       `:'. Example: The string(3,n) "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(7,n,1 builtins) the mode for an emacs-style binding.  If your
       terminal sends characters, that cause you to abort(3,7) 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(3,n) you do  not
       want to use the `H' or `L' commands any longer.  As shown in(1,8) this exam-
       ple, multiple keys can be assigned to one function in(1,8) a  single  state-
       ment.

       maxwin num

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

       meta

       Insert the command  character  (C-a)  in(1,8)  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(1,8) the status line at the
       first sign of output and the window will also be marked with an `@'  in(1,8)
       the  window-status  display.   Monitoring is initially off for all win-
       dows.

       msgminwait sec

       Defines the time(1,2,n) screen delays a new message when one message  is  cur-
       rently displayed.  The default is 1 second.

       msgwait sec

       Defines  the  time(1,2,n) a message is displayed if(3,n) 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(1,5)
       accessing this screen session.

       nethack on|off

       Changes the kind of error(8,n) messages used by screen.  When you are famil-
       iar with the game "nethack", you may enjoy the  nethack-style  messages
       which will often blur the facts a little, but are much funnier to read.
       Anyway, standard messages often tend to be unclear as well.
       This option is only available if(3,n) 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(2,8) output. This can happen if(3,n) a user presses ^S or a TCP/modem con-
       nection gets(3,n) cut but no hangup is received. If nonblock is off (this is
       the default) screen waits until the display restarts to accept(2,8) the out-
       put.  If  nonblock is on, screen waits until the timeout(1,3x,3x cbreak) 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(1,2,n) it restarts to accept(2,8) 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(2,n,1 builtins) from the windows. The default value is 256. If
       you have a fast display (like xterm), you can set(7,n,1 builtins)  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(1,8) your ".screenrc" file(1,n) and screen will ask
       for  it, whenever someone attempts to resume a detached. This is useful
       if(3,n) you have privileged programs running under screen and  you  want  to
       protect  your session from reattach attempts by another user masquerad-
       ing as your uid (i.e. any superuser.)  If no crypted password is speci-
       fied, screen prompts twice for typing a password and places its encryp-
       tion in(1,8) 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(1,3) of the current window. The register '.' is treated  as  the
       paste  buffer. If no parameter is given the user is prompted for a sin-
       gle register to paste.  The paste buffer can be filled with  the  copy,
       history(1,3,n,1 builtins)  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(5,8) 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(1,8)  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(2,n)  a  break  condition.  See
       `break'.

       pow_detach

       Power  detach.  Mainly the same as detach, but also sends a HANGUP sig-
       nal(2,7) to the parent process of screen.  CAUTION: This will  result  in(1,8)  a
       logout, when screen was started from your login(1,3,5) shell.

       pow_detach_msg [message]

       The message specified here is output whenever a `Power detach' was per-
       formed. It may be used as a replacement for  a  logout  message  or  to
       reset(1,7,1 tput) 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(3,n), screen will not use the terminal capa-
       bilities "po/pf" if(3,n) it detects an ansi print sequence ESC [  5  i,  but
       pipe(2,8) 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(1,2)  access(2,5)
       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(3,n)  it had been typed in(1,8) from the user's keyboard. This
       command can be used to bind(2,n,1 builtins) multiple actions to a single key.

       quit

       Kill all windows and terminate screen.  Note that on VT100-style termi-
       nals  the keys C-4 and C-\ are identical.  This makes the default bind-
       ings dangerous: Be careful not to type C-a C-4  when  selecting  window
       no.  4.  Use the empty bind(2,n,1 builtins) command (as in(1,8) "bind(2,n,1 builtins) '^\'") to remove a key
       binding.

       readbuf [-e encoding(3,n)] [filename]

       Reads the contents of the specified file(1,n) into the  paste  buffer.   You
       can tell screen the encoding(3,n) of the file(1,n) via the -e option.  If no file(1,n)
       is specified, the screen-exchange filename is used.  See also  "buffer-
       file(1,n)" command.

       readreg [-e encoding(3,n)] [register [filename]]

       Does  one of two things, dependent on number of arguments: with zero or
       one arguments it it duplicates the paste buffer contents into the  reg-
       ister  specified  or entered at the prompt. With two arguments it reads
       the contents of the named(5,8) file(1,n) into the register, just as readbuf reads
       the  screen-exchange  file(1,n)  into the paste buffer.  You can tell screen
       the encoding(3,n) of the file(1,n) via the -e option.  The following example will
       paste the system's password file(1,n) into the screen window (using register
       p, where a copy remains):

                   C-a : readreg p /etc/passwd(1,5)
                   C-a : paste p

       redisplay

       Redisplay the current window. Needed to get a full  redisplay  when  in(1,8)
       partial redraw mode.

       register [-e encoding(3,n)] key string(3,n)

       Save  the  specified  string(3,n)  to the register key.  The encoding(3,n) of the
       string(3,n) can be specified via the -e option.  See also the  "paste"  com-
       mand.

       remove

       Kill the current region. This is a no-op if(3,n) there is only one region.

       removebuf

       Unlinks  the  screen-exchange  file(1,n) used by the commands "writebuf" and
       "readbuf".

       reset(1,7,1 tput)

       Reset the virtual(5,8)  terminal  to  its  "power-on"  values.  Useful  when
       strange  settings  (like  scroll regions or graphics character set(7,n,1 builtins)) 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(3,n) 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(7,n,1 builtins) 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(1,3,5) options (-l and -ln) , terminal type
       option (-T <term(5,7)>), 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(1,8) the range 0..9 is given,
       the window number n is assigned to the newly  created  window  (or,  if(3,n)
       this  number  is already in-use, the next available number).  If a com-
       mand is specified after "screen", this command (with  the  given  argu-
       ments)  is started in(1,8) the window; otherwise, a shell is created.  Thus,
       if(3,n) your ".screenrc" contains the lines

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

       screen creates a shell window (in(1,8) window #1) and a window with a TELNET
       connection  to the machine foobar (with no flow-control using the title
       "foobar" in(1,8) window #2) and will write(1,2) a logfile ("screenlog.2") of  the
       telnet session.  Note, that unlike previous versions of screen no addi-
       tional default window is created when "screen" commands are included in(1,8)
       your  ".screenrc"  file.  When  the initialization is completed, screen
       switches to the last window specified in(1,8) your  .screenrc  file(1,n)  or,  if(3,n)
       none, opens a default window #0.
       Screen  has built in(1,8) some functionality of "cu" and "telnet".  See also
       chapter "WINDOW TYPES".

       scrollback num

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

       select(2,7,2 select_tut) [WindowID]

       Switch to the window identified by WindowID.  This can be a prefix of a
       window title (alphanumeric window name) or a window number.  The param-
       eter is optional and if(3,n) 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(2,7,2 select_tut)  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(3,n) used with screen's "-X" option.

       sessionname [name]

       Rename the current session. Note, that  for  "screen  -list"  the  name
       shows up with the process-id prepended. If the argument "name" is omit-
       ted, the name of this session is displayed. Caution: The $STY  environ-
       ment  variables  still reflects the old name. This may result in(1,8) confu-
       sion.  The default is constructed from the tty(1,4) and host(1,5) names.

       setenv [var [string(3,n)]]

       Set the environment variable var to value string(3,n).  If only var is spec-
       ified,  the  user  will be prompted to enter a value.  If no parameters
       are specified, the user will be prompted for both variable  and  value.
       The environment is inherited by all subsequently forked shells.

       setsid(2,8) [on|off]

       Normally screen uses different sessions and process groups for the win-
       dows. If setsid(2,8) is turned off, this is not done anymore and all windows
       will  be  in(1,8) 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(1,8) 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(3,n) you'd like
       to  run a tty-enhancer which is expecting to execute the program speci-
       fied in(1,8) $SHELL. If the command begins with a '-' character,  the  shell
       will be started as a login-shell.

       shelltitle title

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

       silence [on|off|sec]

       Toggles  silence  monitoring of windows.  When silence is turned on and
       an affected window is switched into the background,  you  will  receive
       the  silence  notification message in(1,8) the status line after a specified
       period of inactivity (silence). The default timeout(1,3x,3x cbreak) 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(1,2,n) that all windows  monitored  for  silence  should  wait
       before displaying a message. Default 30 seconds.

       sleep(1,3) num

       This  command will pause the execution of a .screenrc file(1,n) for num sec-
       onds.  Keyboard activity will end the sleep.  It may be  used  to  give
       users(1,5) a chance to read(2,n,1 builtins) the messages output by "echo(1,3x,1 builtins)".

       slowpaste msec

       Define  the  speed at which text is inserted into the current window by
       the paste ("C-a ]") command.  If the slowpaste value is nonzero text is
       written  character by character.  screen will make a pause of msec mil-
       liseconds after each single character write(1,2) to allow the application to
       process its input. Only use slowpaste if(3,n) your underlying system exposes
       flow control problems while pasting large amounts of text.

       source file(1,n)

       Read and execute commands from file(1,n) file(1,n). Source commands may be nested
       to  a  maximum  recursion level of ten. If file(1,n) is not an absolute path
       and screen is already processing a source command, the parent directory
       of  the  running source command file(1,n) is used to search for the new com-
       mand file(1,n) before screen's current directory.

       Note that termcap/terminfo/termcapinfo commands only  work  at  startup
       and  reattach  time(1,2,n),  so  they must be reached via the default screenrc
       files to have an effect.

       sorendition [attr(1,5) [color]]

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

       split(1,n)

       Split the current region into two new ones. All regions on the  display
       are  resized  to make room for the new region. The blank window is dis-
       played on the new region. Use the "remove" or  the  "only"  command  to
       delete regions.

       startup_message on|off

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

       stuff string(3,n)

       Stuff the string(3,n) string(3,n) in(1,8) the input  buffer  of  the  current  window.
       This is like the "paste" command but with much less(1,3) overhead.  You can-
       not paste large buffers with the "stuff" command. It is most useful for
       key bindings. See also "bindkey".

       su [username [password [password2]]

       Substitute  the  user of a display. The command prompts for all parame-
       ters that are omitted. If passwords are specified as  parameters,  they
       have  to be specified un-crypted. The first password is matched against
       the systems passwd(1,5) database, the second password is matched against the
       screen  password as set(7,n,1 builtins) 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(2,5) to the commands
       available for user nobody.  These are "detach",  "license",  "version(1,3,5)",
       "help" and "displays".

       suspend

       Suspend  screen.  The windows are in(1,8) the `detached' state, while screen
       is suspended. This feature relies on the shell being  able  to  do  job
       control.

       term(5,7) term(5,7)

       In each window's environment screen opens, the $TERM variable is set(7,n,1 builtins) to
       "screen" by default.  But when no description for "screen" is installed
       in(1,8)  the  local  termcap or terminfo data base, you set(7,n,1 builtins) $TERM to - say -
       "vt100". This won't do much harm, as screen is  VT100/ANSI  compatible.
       The  use  of the "term(5,7)" 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(5,7) terminal-tweaks [window-tweaks]
       terminfo term(5,7) terminal-tweaks [window-tweaks]
       termcapinfo term(5,7) terminal-tweaks [window-tweaks]

       Use  this command to modify your terminal's termcap entry without going
       through all the hassles involved in(1,8) creating a  custom  termcap  entry.
       Plus,  you  can optionally customize the termcap generated for the win-
       dows.  You have to place these commands in(1,8) one of the screenrc  startup
       files, as they are meaningless once the terminal emulator is booted.
       If  your  system  works uses the terminfo database rather than termcap,
       screen will understand the  `terminfo'  command,  which  has  the  same
       effects  as the `termcap' command.  Two separate commands are provided,
       as there are subtle syntactic differences, e.g. when parameter interpo-
       lation (using `%') is required. Note that termcap names of the capabil-
       ities have to be used with the `terminfo' command.
       In many cases, where the arguments are valid in(1,8) both terminfo and term-
       cap  syntax,  you  can  use  the command `termcapinfo', which is just a
       shorthand for a pair of `termcap' and `terminfo' commands with  identi-
       cal arguments.

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

       Each tweak argument contains one or more termcap defines (separated  by
       `:'s)  to  be  inserted  at the start of the appropriate termcap entry,
       enhancing it or overriding existing values.  The first  tweak  modifies
       your  terminal's  termcap,  and contains definitions that your terminal
       uses to perform certain functions.  Specify a null string(3,n) to leave this
       unchanged (e.g. '').  The second (optional) tweak modifies all the win-
       dow termcaps, and should contain definitions  that  screen  understands
       (see the "VIRTUAL TERMINAL" section).

       Some examples:

              termcap xterm*  LP:hs@

       Informs  screen  that  all  terminals that begin with `xterm' have firm
       auto-margins that allow the last position on the screen to  be  updated
       (LP), but they don't really have a status line (no 'hs' - append `@' to
       turn entries off).  Note that we assume `LP'  for  all  terminal  names
       that  start  with "vt", but only if(3,n) 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(1,n) into (Z0) and back out of (Z1) 132-character-per-line mode if(3,n)
       this  is a VT102 or VT220.  (You must specify Z0 and Z1 in(1,8) 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(1,8)  the
       `im' string(3,n) is after the `=', so it is part of the string(3,n)).  Having the
       `im' and `ei' definitions put into your terminal's termcap  will  cause
       screen  to  automatically  advertise the character-insert capability in(1,8)
       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(7,n,1 builtins) the $SCREENCAP variable  prior  to  running  screen.
       See  the  discussion  on the "VIRTUAL TERMINAL" in(1,8) this manual, and the
       termcap(5) man(1,5,7) page for more information on termcap definitions.

       time(1,2,n) [string(3,n)]

       Uses the message line to display the time(1,2,n) of day, the  host(1,5)  name,  and
       the  load(7,n)  averages  over 1, 5, and 15 minutes (if(3,n) this is available on
       your system).  For window specific information use "info(1,5,n)".

       If a string(3,n) is specified, it changes the format of the time(1,2,n) report like
       it  is described in(1,8) the "STRING ESCAPES" chapter. Screen uses a default
       of "%c:%s %M %d %H%? %l%?".

       title [windowtitle]

       Set the name of the current window to windowtitle. If no name is speci-
       fied, screen prompts for one. This command was known as `aka' in(1,8) previ-
       ous releases.

       unsetenv var

       Unset an environment variable.

       utf8 [on|off [on|off]]

       Change the encoding(3,n) used in(1,8) the current window. If utf8 is enabled, the
       strings  sent to the window will be UTF-8 encoded and vice versa. Omit-
       ting the parameter toggles the setting. If a second parameter is given,
       the display's encoding(3,n) 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(1,8) 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(3,n)
       the window receives a bell character (^G), vbell is set(7,n,1 builtins)  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(1,8) seconds after each display of  screen's  visual  bell
       message. The default is 1 second.

       verbose [on|off]

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

       version(1,3,5)

       Print the current version(1,3,5) and the compile date in(1,8) the status line.

       wall message

       Write  a message to all displays. The message will appear in(1,8) the termi-
       nal's status line.

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

       Toggle the window width between 80 and 132 columns or set(7,n,1 builtins)  it  to  cols
       columns  if(3,n) 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(3,n) you want to
       change both values.  The -w option tells screen to  leave  the  display
       size unchanged and just set(7,n,1 builtins) the window size, -d vice versa.

       windowlist [-b] [-m]
       windowlist string(3,n) [string(3,n)]
       windowlist title [title]

       Display all windows in(1,8) 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(1,n) 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(3,n) and title option, the
       title is displayed as table heading, while the lines are made by  using
       the  string(3,n)  setting.  The default setting is "Num Name%=Flags" for the
       title and "%3n %t%=%f" for the lines.  See the "STRING ESCAPES" chapter
       for more codes (e.g. color settings).

       windows

       Uses  the message line to display a list of all the windows.  Each win-
       dow is listed by number with the name of process that has been  started
       in(1,8)  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(1,8)"  are  marked  with  a  `$';  a  background window that has
       received a bell is marked with a `!'; a background window that is being
       monitored  and  has  had activity occur is marked with an `@'; a window
       which has output logging turned on is marked with `(L)'; windows  occu-
       pied  by  other  users(1,5) are marked with `&'; windows in(1,8) the zombie state
       are marked with `Z'.  If this list is too long to fit on the terminal's
       status line only the portion around the current window is displayed.

       wrap [on|off]

       Sets  the  line-wrap setting for the current window.  When line-wrap is
       on, the second consecutive printable character output at the last  col-
       umn  of  a  line  will  wrap to the start of the following line.  As an
       added feature, backspace (^H) will also wrap through the left margin to
       the previous line.  Default is `on'.

       writebuf [-e encoding(3,n)] [filename]

       Writes  the  contents of the paste buffer to the specified file(1,n), or the
       public accessible screen-exchange file(1,n) if(3,n) no filename is given. This is
       thought  of  as a primitive means of communication between screen users(1,5)
       on the same host. If an encoding(3,n)  is  specified  the  paste  buffer  is
       recoded on the fly to match the encoding.  The filename can be set(7,n,1 builtins) with
       the bufferfile command and defaults to "/tmp/screen-exchange".

       writelock [on|off|auto(5,8)]

       In addition to access(2,5) control lists, not all users(1,5) may be able to write(1,2)
       to  the  same  window at once. Per default, writelock is in(1,8) `auto(5,8)' mode
       and grants exclusive input permission to the user who is the  first  to
       switch(1,n) to the particular window. When he leaves the window, other users(1,5)
       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(1,2)  permission
       while switching to other windows.

       xoff
       xon

       Insert  a  CTRL-s  / CTRL-q character to the stdin queue(1,3) of the current
       window.

       zmodem [off|auto(5,8)|catch|pass]
       zmodem sendcmd [string(3,n)]
       zmodem recvcmd [string(