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SCREEN(1)                                                                                          SCREEN(1)

       screen - screen manager with VT100/ANSI terminal emulation

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

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

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

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

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

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

              screen emacs prog.c

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

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

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

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

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

       Screen has the following command-line options:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

       -v   Print version number.

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

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

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

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

       The following table shows the default key bindings:

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

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

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

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

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

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

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

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

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

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

       C-a C       (clear)       Clear the screen.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

       C-a ?       (help)        Show key bindings.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

       The following commands are available:

       acladd usernames [crypted-pw]
       addacl usernames

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

       aclchg usernames permbits list
       chacl usernames permbits list

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

       acldel username

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

       aclgrp username [groupname]

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

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

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

       activity message

       When  any activity occurs in a background window that is being monitored, screen displays a notifica-tion notification
       tion in the message line.  The notification message can be re-defined by means of the "activity" com-mand. command.
       mand.   Each  occurrence  of `%' in message is replaced by the number of the window in which activity
       has occurred, and each occurrence of `^G' is replaced by the definition  for  bell  in  your  termcap
       (usually an audible bell).  The default message is

                   'Activity in window %n'

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

       allpartial on|off

       If set to on, only the current cursor line is refreshed on window change.  This affects  all  windows
       and  is  useful for slow terminal lines. The previous setting of full/partial refresh for each window
       is restored with "allpartial off".  This is a global flag that immediately takes effect on  all  win-dows windows
       dows  overriding the "partial" settings. It does not change the default redraw behavior of newly cre-ated created
       ated windows.

       altscreen on|off

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

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

       Execute  a  command  at  other displays or windows as if it had been entered there.  "At" changes the
       context (the `current window' or `current display' setting) of the command. If  the  first  parameter
       describes  a  non-unique context, the command will be executed multiple times. If the first parameter
       is of the form `identifier*' then identifier is matched against user names.  The command is  executed
       once  for  each  display of the selected user(s). If the first parameter is of the form `identifier%'
       identifier is matched against displays. Displays are named after the ttys  they  attach.  The  prefix
       `/dev/'  or  `/dev/tty'  may  be  omitted  from  the  identifier.  If identifier has a `#' or nothing
       appended it is matched against window numbers and titles. Omitting an identifier in front of the `#',
       `*' or `%'-character selects all users, displays or windows because a prefix-match is performed. Note
       that on the affected display(s) a short message will describe what happened.  Permission  is  checked
       for  initiator of the "at" command, not for the owners of the affected display(s).  Note that the '#'
       character works as a comment introducer when it is preceded by whitespace. This  can  be  escaped  by
       prefixing  a '\'.  Permission is checked for the initiator of the "at" command, not for the owners of
       the affected display(s).
       Caveat: When matching against windows, the command is executed at least  once  per  window.  Commands
       that change the internal arrangement of windows (like "other") may be called again. In shared windows
       the command will be repeated for each attached display. Beware, when  issuing  toggle  commands  like
       "login"!   Some  commands  (e.g. "process") require that a display is associated with the target win-dows. windows.
       dows.  These commands may not work correctly under "at" looping over windows.

       attrcolor attrib [attribute/color-modifier]

       This command can be used to highlight attributes by changing the color of the text. If the  attribute
       attrib  is  in  use, the specified attribute/color modifier is also applied. If no modifier is given,
       the current one is deleted. See the "STRING ESCAPES" chapter for the syntax of the  modifier.  Screen
       understands  two  pseudo-attributes, "i" stands for high-intensity foreground color and "I" for high-intensity highintensity
       intensity background color.


              attrcolor b "R"

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

              attrcolor u "-u b"

       Use blue text instead of underline.

              attrcolor b ".I"

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

              attrcolor i "+b"

       Make bright colored text also bold.

       autodetach on|off

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

       autonuke on|off

       Sets whether a clear screen sequence should nuke all the output that has not been written to the ter-minal. terminal.
       minal. 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 sub-stitution substitution
       stitution of the "%`" string escape. The specified lifespan is the number of seconds  the  output  is
       considered  valid.  After  this  time,  the  command is run again if a corresponding string escape is
       encountered.  The autorefresh parameter triggers an automatic  refresh  for  caption  and  hardstatus
       strings after the specified number of seconds. Only the last line of output is used for substitution.
       If both the lifespan and the autorefresh parameters are zero, the backtick  program  is  expected  to
       stay  in  the  background and generate output once in a while.  In this case, the command is executed
       right away and screen stores the last line of output. If a new line gets printed screen will automat-ically automatically
       ically refresh the hardstatus or the captions.
       The second form of the command deletes the backtick command with the numerical id id.

       bce [on|off]

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

       bell_msg [message]

       When  a  bell character is sent to a background window, screen displays a notification in the message
       line.  The notification message can be re-defined by this command.  Each occurrence of `%' in message
       is replaced by the number of the window to which a bell has been sent, and each occurrence of `^G' is
       replaced by the definition for bell in your termcap (usually an audible bell).  The  default  message

                   'Bell in window %n'

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

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

       Bind a command to a key.  By default, most of the commands provided by screen are  bound  to  one  or
       more keys as indicated in the "DEFAULT KEY BINDINGS" section, e.g. the command to create a new window
       is bound to "C-c" and "c".  The "bind" command can be used to redefine the key bindings and to define
       new  bindings.   The  key argument is either a single character, a two-character sequence of the form
       "^x" (meaning "C-x"), a backslash followed by an octal number (specifying the ASCII code of the char-acter), character),
       acter),  or  a backslash followed by a second character, such as "\^" or "\\".  The argument can also
       be quoted, if you like.  If no further argument is given, any previously established binding for this
       key is removed.  The command argument can be any command listed in this section.

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

       Some examples:

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

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

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

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

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

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

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

       This command manages screen's input translation tables. Every entry in one of the tables tells screen
       how  to  react  if  a certain sequence of characters is encountered. There are three tables: one that
       should contain actions programmed by the user, one for the default actions used for  terminal  emula-tion emulation
       tion and one for screen's copy mode to do cursor movement. See section "INPUT TRANSLATION" for a list
       of default key bindings.
       If the -d option is given, bindkey modifies the default table, -m changes the  copy  mode  table  and
       with neither option the user table is selected.  The argument string is the sequence of characters to
       which an action is bound. This can either be a fixed string or a  termcap  keyboard  capability  name
       (selectable with the -k option).
       Some  keys  on a VT100 terminal can send a different string if application mode is turned on (e.g the
       cursor keys).  Such keys have two entries in the translation table. You can  select  the  application
       mode entry by specifying the -a option.
       The  -t  option  tells  screen  not to do inter-character timing. One cannot turn off the timing if a
       termcap capability is used.
       Cmd can be any of screen's commands with an arbitrary number of args.  If cmd  is  omitted  the  key-binding keybinding
       binding is removed from the table.
       Here are some examples of keyboard bindings:

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

               bindkey -k k1 select 1
       Make the "F1" key switch to window one.

               bindkey -t foo stuff barfoo
       Make "foo" an abbreviation of the word "barfoo". Timeout is disabled so that users can type slowly.

               bindkey "\024" mapdefault
       This key-binding makes "^T" an escape character for key-bindings. If you did the above "stuff barfoo"
       binding, you can enter the word "foo" by typing "^Tfoo". If you want to insert a  "^T"  you  have  to
       press the key twice (i.e. escape the escape binding).

               bindkey -k F1 command
       Make the F11 (not F1!) key an alternative screen escape (besides ^A).

       break [duration]

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


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

       blankerprg [program args]

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

       breaktype [tcsendbreak|TIOCSBRK |TCSBRK]

       Choose one of the available methods of generating a break signal for terminal devices.  This  command
       should  affect  the current window only.  But it still behaves identical to "defbreaktype". This will
       be changed in the future.  Calling "breaktype" with no parameter displays the break  method  for  the
       current window.

       bufferfile [exchange-file]

       Change  the filename used for reading and writing with the paste buffer.  If the optional argument to
       the "bufferfile" command is omitted, the default  setting  ("/tmp/screen-exchange")  is  reactivated.
       The  following  example will paste the system's password file into the screen window (using the paste
       buffer, where a copy remains):

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

       c1 [on|off]

       Change c1 code processing. "C1 on" tells screen to treat the input characters between 128 and 159  as
       control  functions.   Such  an  8-bit  code is normally the same as ESC followed by the corresponding
       7-bit code. The default setting is to process c1 codes and can be changed with the  "defc1"  command.
       Users with fonts that have usable characters in the c1 positions may want to turn this off.

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

       This  command  controls  the  display of the window captions. Normally a caption is only used if more
       than one window is shown on the display (split screen mode). But if the type is set to always  screen
       shows a caption even if only one window is displayed. The default is splitonly.

       The  second  form  changes  the  text  used for the caption. You can use all escapes from the "STRING
       ESCAPES" chapter. Screen uses a default of `%3n %t'.

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

       charset set

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

       chdir [directory]

       Change  the current directory of screen to the specified directory or, if called without an argument,
       to your home directory (the value of the environment variable $HOME).  All windows that  are  created
       by means of the "screen" command from within ".screenrc" or by means of "C-a : screen ..." or "C-a c"
       use this as their default directory.  Without a chdir command, this would be the directory from which
       screen was invoked.  Hardcopy and log files are always written to the window's default directory, not
       the current directory of the process running in the window.  You can use this command multiple  times
       in your .screenrc to start various windows in different default directories, but the last chdir value
       will affect all the windows you create interactively.


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

       colon [prefix]

       Allows you to enter ".screenrc" command lines. Useful for on-the-fly modification  of  key  bindings,
       specific window creation and changing settings. Note that the "set" keyword no longer exists! Usually
       commands affect the current window rather than default settings for future windows.  Change  defaults
       with commands starting with 'def...'.

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

       command [-c class]

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

       compacthist [on|off]

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

       console [on|off]

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


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

           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.

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

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

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

       copy_reg [key]

       No longer exists, use "readreg" instead.

       crlf [on|off]

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

       debug on|off

       Turns  runtime  debugging on or off. If screen has been compiled with option -DDEBUG debugging avail-able available
       able 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 for-ever. forever.

       defc1 on|off

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

       defautonuke on|off

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

       defbce on|off

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

       defbreaktype [tcsendbreak|TIOCSBRK |TCSBRK]

       Choose one of the available methods of generating a break signal for terminal devices. The  preferred
       methods  are tcsendbreak and TIOCSBRK.  The third, TCSBRK, blocks the complete screen session for the
       duration of the break, but it may be the only way to generate long breaks.  Tcsendbreak and  TIOCSBRK
       may  or  may  not produce long breaks with spikes (e.g. 4 per second). This is not only system depen-dant, dependant,
       dant, this also differs between serial board drivers.  Calling "defbreaktype" with no parameter  dis-plays displays
       plays the current setting.

       defcharset [set]

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

       defescape xy

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

       defflow on|off|auto [interrupt]

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

       defgr on|off

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

       defhstatus [status]

       The hardstatus line that all new windows will get is set to status.  This command is useful  to  make
       the  hardstatus  of  every window display the window number or title or the like.  Status may contain
       the same directives as in the window messages, but the directive escape character is '^E' (octal 005)
       instead  of  '%'.   This  was  done to make a misinterpretation of program generated hardstatus lines
       impossible.  If the parameter status is omitted,  the  current  default  string  is  displayed.   Per
       default the hardstatus line of new windows is empty.

       defencoding enc

       Same as the encoding command except that the default setting for new windows is changed. Initial set-ting setting
       ting is the encoding taken from the terminal.

       deflog on|off

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

       deflogin on|off

       Same  as  the  login command except that the default setting for new windows is changed. This is ini-tialized initialized
       tialized with `on' as distributed (see

       defmode mode

       The mode of each newly allocated pseudo-tty is set to mode.  Mode is an octal number.  When no  "def-mode" "defmode"
       mode" 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 set-ting setting
       ting is `off'.

       defnonblock on|off|numsecs

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

       defobuflimit limit

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

       defscrollback num

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

       defshell command

       Synonym to the shell command. See there.

       defsilence on|off

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

       defslowpaste msec"

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

       defutf8 on|off

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

       defwrap on|off

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

       defwritelock on|off|auto

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

       defzombie [keys]

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

       detach [-h]

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


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


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

       digraph [preset]

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


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

       echo [-n] message

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

       encoding enc [enc]

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

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

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

       escape xy

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

       eval command1 [command2 ...]

       Parses and executes each argument as separate command.

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

       Run  a unix subprocess (specified by an executable path newcommand and its optional arguments) in the
       current window. The flow of data between  newcommands  stdin/stdout/stderr,  the  process  originally
       started in the window (let us call it "application-process") and screen itself (window) is controlled
       by the filedescriptor pattern fdpat.  This pattern is basically a three character sequence represent-ing representing
       ing  stdin,  stdout  and  stderr of newcommand. A dot (.) connects the file descriptor to screen.  An
       exclamation mark (!) causes the file descriptor to be connected to the application-process.  A  colon
       (:)  combines  both.   User  input  will go to newcommand unless newcommand receives the application-process' applicationprocess'
       process' output (fdpats first character is `!' or `:') or a pipe symbol (|) is  added  (as  a  fourth
       character) to the end of fdpat.
       Invoking  `exec'  without  arguments  shows name and arguments of the currently running subprocess in
       this window. Only one subprocess a time can be running in each window.
       When a subprocess is running the `kill' command will affect it instead of the windows process.
       Refer to the postscript file `doc/' for a confusing illustration of all 21 possible  combina-tions. combinations.
       tions. Each drawing shows the digits 2,1,0 representing the three file descriptors of newcommand. The
       box marked `W' is the usual pty that has the application-process on its slave side.  The  box  marked
       `P' is the secondary pty that now has screen at its master side.

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


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

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

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

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

              exec !..| less

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

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

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


       Change  the  window  size  to  the  size of the current region. This command is needed because screen
       doesn't adapt the window size automatically if the window is displayed more than once.

       flow [on|off|auto]

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

       focus [up|down|top|bottom]

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

       gr [on|off]

       Turn GR charset switching on/off. Whenever screen sees an input character with the 8th  bit  set,  it
       will  use  the  charset  stored in the GR slot and print the character with the 8th bit stripped. The
       default (see also "defgr") is not to process GR switching  because  otherwise  the  ISO88591  charset
       would not work.

       hardcopy [-h] [file]

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

       hardcopy_append on|off

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

       hardcopydir directory

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

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

       This command configures the use and emulation of the terminal's hardstatus line. The first form  tog-gles toggles
       gles  whether  screen  will  use  the hardware status line to display messages. If the flag is set to
       `off', these messages are overlaid in reverse video mode at the display line. The default setting  is

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

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

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

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

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

       help [-c class]

       Not really a online help, but displays a help screen showing you all the  key  bindings.   The  first
       pages  list all the internal commands followed by their current bindings.  Subsequent pages will dis-play display
       play the custom commands, one command per key.  Press space when you're done reading  each  page,  or
       return  to  exit  early.   All other characters are ignored. If the "-c" option is given, display all
       bound commands for the specified command class.  See also "DEFAULT KEY BINDINGS" section.


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

       hstatus status

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

       idle [timeout [cmd args]]

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

       ignorecase [on|off]

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


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

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

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

       The  currently active character set (G_, G1, G2, or G3) and in square brackets the terminal character
       sets that are currently designated as G_ through G3 is shown. If the window is  in  UTF-8  mode,  the
       string "UTF-8" is shown instead.

       Additional modes depending on the type of the window are displayed at the end of the status line (See
       also chapter "WINDOW TYPES").
       If the state machine of the terminal emulator is in a non-default state, the  info  line  is  started
       with a string identifying the current state.
       For system information use the "time" command.

       ins_reg [key]

       No longer exists, use "paste" instead.


       Kill current window.
       If there is an `exec' command running then it is killed. Otherwise the process (shell) running in the
       window receives a HANGUP condition, the  window  structure  is  removed  and  screen  (your  display)
       switches  to  another  window.  When the last window is destroyed, screen exits.  After a kill screen
       switches to the previously displayed window.
       Note: Emacs users should keep this command in mind, when killing a line.  It is  recommended  not  to
       use "C-a" as the screen escape key or to rebind kill to "C-a K".


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


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


       Lock this display.  Call a screenlock program (/local/bin/lck or /usr/bin/lock or  a  builtin  if  no
       other is available). Screen does not accept any command keys until this program terminates. Meanwhile
       processes in the windows may continue, as the windows are in the  `detached'  state.  The  screenlock
       program may be changed through the environment variable $LOCKPRG (which must be set in the shell from
       which screen is started) and is executed with the user's uid and gid.
       Warning: When you leave other shells unlocked and you have no password set on  screen,  the  lock  is
       void:  One could easily re-attach from an unlocked shell. This feature should rather be called `lock-terminal'. `lockterminal'.

       log [on|off]

       Start/stop writing output of the current window to a  file  "screenlog.n"  in  the  window's  default
       directory,  where  n is the number of the current window. This filename can be changed with the `log-file' `logfile'
       file' command. If no parameter is given, the state of logging is toggled. The session log is appended
       to  the  previous contents of the file if it already exists. The current contents and the contents of
       the scrollback history are not included in the session log.  Default is `off'.

       logfile filename
       logfile flush secs

       Defines the name the logfiles will get. The default is "screenlog.%n". The second  form  changes  the
       number of seconds screen will wait before flushing the logfile buffer to the file-system. The default
       value is 10 seconds.

       login [on|off]

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

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

       This command controls logfile time-stamp mechanism of screen.  If time-stamps are turned "on", screen
       adds  a string containing the current time to the logfile after two minutes of inactivity.  When out-put output
       put continues and more than another two minutes have passed, a second time-stamp is added to document
       the restart of the output. You can change this timeout with the second form of the command. The third
       form is used for customizing the time-stamp string (`-- %n:%t -- time-stamp -- %M/%d/%y  %c:%s  --\n'
       by default).


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


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

       maptimeout [timo]

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

       markkeys string

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

       maxwin num

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


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

       monitor [on|off]

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

       msgminwait sec

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

       msgwait sec

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

       multiuser on|off

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

       nethack on|off

       Changes the kind of error messages used by screen.  When you are familiar with  the  game  "nethack",
       you  may enjoy the nethack-style messages which will often blur the facts a little, but are much fun-nier funnier
       nier to read. Anyway, standard messages often tend to be unclear as well.
       This option is only available if screen was compiled with the NETHACK flag defined. The default  set-ting setting
       ting is then determined by the presence of the environment variable $NETHACKOPTIONS.


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

       nonblock [on|off|numsecs]

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

       number [n]

       Change the current windows number. If the given number n is already used by another window, both win-dows windows
       dows  exchange  their  numbers. If no argument is specified, the current window number (and title) is

       obuflimit [limit]

       If the output buffer contains more bytes than the specified limit, no more data will be read from the
       windows.  The  default  value is 256. If you have a fast display (like xterm), you can set it to some
       higher value. If no argument is specified, the current setting is displayed.


       Kill all regions but the current one.


       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 all-partial allpartial
       partial  command.  Default is `off', of course.  This default is fixed, as there is currently no def-partial defpartial
       partial command.

       password [crypted_pw]

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

       paste [registers [dest_reg]]

       Write  the  (concatenated) contents of the specified registers to the stdin queue of the current win-dow. window.
       dow. The register '.' is treated as the paste buffer. If no parameter is given the user  is  prompted
       for  a  single  register to paste.  The paste buffer can be filled with the copy, history and readbuf
       commands.  Other registers can be filled with the register, readreg and paste commands.  If paste  is
       called  with a second argument, the contents of the specified registers is pasted into the named des-tination destination
       tination 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 regis-ters registers
       ters (not the paste buffer) then there need not be a current display (terminal attached), as the reg-isters registers
       isters are a global resource. The paste buffer exists once for every user.

       pastefont [on|off]

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


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


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

       pow_detach_msg [message]

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


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

       printcmd [cmd]

       If cmd is not an empty string, screen will not use the terminal capabilities "po/pf" if it detects an
       ansi print sequence ESC [ 5 i, but pipe the output into cmd.  This should normally be a command  like
       "lpr" or "'cat > /tmp/scrprint'".  printcmd without a command displays the current setting.  The ansi
       sequence ESC \ ends printing and closes the pipe.
       Warning: Be careful with this command! If other user have write access to your terminal, they will be
       able to fire off print commands.

       process [key]

       Stuff  the  contents of the specified register into screen's input queue. If no argument is given you
       are prompted for a register name. The text is parsed as if it had been typed in from the user's  key-board. keyboard.
       board. This command can be used to bind multiple actions to a single key.


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

       readbuf [-e encoding] [filename]

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

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

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

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


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

       register [-e encoding] key string

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


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


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


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


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

              resize +N   increase current region height by N

              resize -N   decrease current region height by N

              resize  N   set current region height to N

              resize  =   make all windows equally high

              resize  max maximize current region height

              resize  min minimize current region height

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

       Establish  a  new  window.   The  flow-control options (-f, -fn and -fa), title (a.k.a.) option (-t),
       login options (-l and -ln) , terminal type option  (-T  <term>),  the  all-capability-flag  (-a)  and
       scrollback option (-h <num>) may be specified with each command.  The option (-M) turns monitoring on
       for this window.  The option (-L) turns output logging on for this window.  If an optional  number  n
       in  the range 0..9 is given, the window number n is assigned to the newly created window (or, if this
       number is already in-use, the next available number).  If a command is specified after "screen", this
       command (with the given arguments) is started in the window; otherwise, a shell is created.  Thus, if
       your ".screenrc" contains the lines

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

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

       scrollback num

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

       select [WindowID]

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

       sessionname [name]

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

       setenv [var [string]]

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

       setsid [on|off]

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

       shell command

       Set the command to be used to create a new shell.  This overrides the value of the environment  vari-able variable
       able  $SHELL.   This  is useful if you'd like to run a tty-enhancer which is expecting to execute the
       program specified in $SHELL. If the command begins with a '-' character, the shell will be started as
       a login-shell.

       shelltitle title

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

       silence [on|off|sec]

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

       silencewait sec

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

       sleep num

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

       slowpaste msec

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

       source file

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

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

       sorendition [attr [color]]

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


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

       startup_message on|off

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

       stuff string

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

       su [username [password [password2]]

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


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

       term term

       In  each  window's  environment  screen opens, the $TERM variable is set to "screen" by default.  But
       when no description for "screen" is installed in the local termcap or terminfo  data  base,  you  set
       $TERM  to  -  say - "vt100". This won't do much harm, as screen is VT100/ANSI compatible.  The use of
       the "term" command is discouraged for non-default purpose.  That is, one may want to specify  special
       $TERM  settings  (e.g.  vt100)  for  the  next  "screen rlogin othermachine" command. Use the command
       "screen -T vt100 rlogin othermachine" rather than setting and resetting the default.

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

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

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

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

       Some examples:

              termcap xterm*  LP:hs@

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

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

       Specifies the firm-margined `LP' capability for all terminals that begin with `vt',  and  the  second
       line  will  also add the escape-sequences to switch into (Z0) and back out of (Z1) 132-character-per-line 132-character-perline
       line mode if this is a VT102 or VT220.  (You must specify Z0 and Z1 in your termcap to use the width-changing widthchanging
       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 endinsert
       insert  (ei) capabilities (the `@' in the `im' string is after the `=', so it is part of the string).
       Having the `im' and `ei' definitions put into your terminal's termcap will cause screen to  automati-cally automatically
       cally  advertise the character-insert capability in each window's termcap.  Each window will also get
       the delete-character capability (dc) added to its termcap, which screen will translate into  a  line-update lineupdate
       update for the terminal (we're pretending it doesn't support character deletion).

       If you would like to fully specify each window's termcap entry, you should instead set the $SCREENCAP
       variable prior to running screen.  See the discussion on the "VIRTUAL TERMINAL" in this  manual,  and
       the termcap(5) man page for more information on termcap definitions.

       time [string]

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

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

       title [windowtitle]

       Set  the  name of the current window to windowtitle. If no name is specified, screen prompts for one.
       This command was known as `aka' in previous releases.

       unsetenv var

       Unset an environment variable.

       utf8 [on|off [on|off]]

       Change the encoding used in the current window. If utf8 is enabled, the strings sent  to  the  window
       will be UTF-8 encoded and vice versa. Omitting the parameter toggles the setting. If a second parame-ter parameter
       ter is given, the display's encoding is also changed (this should rather be done with  screen's  "-U"
       option).  See also "defutf8", which changes the default setting of a new window.

       vbell [on|off]

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

       vbell_msg [message]

       Sets the visual bell message. message is printed to the status line if the  window  receives  a  bell
       character  (^G),  vbell is set to "on", but the terminal does not support a visual bell.  The default
       message is "Wuff, Wuff!!".  Without parameter, the current message is shown.

       vbellwait sec

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

       verbose [on|off]

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


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

       wall message

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

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

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

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

       Display all windows in a table for visual window selection. The desired window can  be  selected  via
       the  standard  movement  keys  (see  the "copy" command) and activated via the return key.  If the -b
       option is given, screen will switch to the blank window before presenting the list, so that the  cur-rent current
       rent  window  is also selectable.  The -m option changes the order of the windows, instead of sorting
       by window numbers screen uses its internal most-recently-used list.

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


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

       wrap [on|off]

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

       writebuf [-e encoding] [filename]

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

       writelock [on|off|auto]

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


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

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

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

       zombie [keys]
       defzombie [keys]

       Per default screen windows are removed from the window list as soon  as  the  windows  process  (e.g.
       shell)  exits.  When  a  string  of  two keys is specified to the zombie command, `dead' windows will
       remain in the list.  The kill command may be used to remove such a window. Pressing the first key  in
       the  dead  window has the same effect. When pressing the second key, screen will attempt to resurrect
       the window. The process that was initially running in the window will be launched again. Calling zom-bie zombie
       bie  without  parameters  will  clear  the  zombie  setting, thus making windows disappear when their
       process exits.

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

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

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

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

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

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

         The normal window contains a shell (default, if no parameter is given) or any other system command
          that could be executed from a shell (e.g.  slogin, etc...)

         If a tty (character special device) name (e.g. "/dev/ttya") is specified as the  first  parameter,
          then  the  window is directly connected to this device.  This window type is similar to "screen cu
          -l /dev/ttya".  Read and write access is required  on  the  device  node,  an  exclusive  open  is
          attempted  on the node to mark the connection line as busy.  An optional parameter is allowed con-sisting consisting
          sisting of a comma separated list of flags in the notation used by stty(1):

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

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

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

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

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

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

          For tty windows, the info command shows some of the modem control lines in the status line.  These
          may  include  `RTS',  `CTS', 'DTR', `DSR', `CD' and more.  This depends on the available ioctl()'s
          and system header files as well as the on the physical capabilities of the serial board.   Signals
          that are logical low (inactive) have their name preceded by an exclamation mark (!), otherwise the
          signal is logical high (active).  Signals not supported by  the  hardware  but  available  to  the
          ioctl() interface are usually shown low.
          When  the  CLOCAL status bit is true, the whole set of modem signals is placed inside curly braces
          ({ and }).  When the CRTSCTS or TIOCSOFTCAR bit is set, the signals `CTS' or  `CD'  are  shown  in
          parenthesis, respectively.

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

         If  the  first parameter is "//telnet", the second parameter is expected to be a host name, and an
          optional third parameter may specify a TCP port number (default decimal 23).  Screen will  connect
          to  a  server  listening  on  the remote host and use the telnet protocol to communicate with that
          For telnet windows, the command info shows details about the connection in square brackets ([  and
          ]) at the end of the status line.

          b      BINARY. The connection is in binary mode.

          e      ECHO. Local echo is disabled.

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

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

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

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

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

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

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

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

       Here is the full list of supported escapes:

       %      the escape character itself

       a      either 'am' or 'pm'

       A      either 'AM' or 'PM'

       c      current time HH:MM in 24h format

       C      current time HH:MM in 12h format

       d      day number

       D      weekday name

       f      flags of the window

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

       h      hardstatus of the window

       H      hostname of the system

       l      current load of the system

       m      month number

       M      month name

       n      window number

       s      seconds

       t      window title

       u      all other users on this window

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

       W      all window numbers and names except the current one

       y      last two digits of the year number

       Y      full year number

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

       :      else part of '%?'

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

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

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

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

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

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

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

       +      add the specified set to the current attributes

       -      remove the set from the current attributes

       !      invert the set in the current attributes

       =      change the current attributes to the specified set

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

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

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

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

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


       "G"    set color to bright green

       "+b r" use bold red

       "= yd" clear all attributes, write in default color on yellow background.

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

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

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

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

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

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

TITLES (naming windows)
       You  can  customize  each window's name in the window display (viewed with the "windows" command (C-a
       w)) by setting it with one of the title commands.  Normally the name displayed is the actual  command
       name  of  the  program created in the window.  However, it is sometimes useful to distinguish various
       programs of the same name or to change the name on-the-fly to reflect the current state of  the  win-dow. window.

       The  default  name  for  all  shell windows can be set with the "shelltitle" command in the .screenrc
       file, while all other windows are created with a "screen" command and thus can have  their  name  set
       with  the -t option.  Interactively, there is the title-string escape-sequence (<esc>kname<esc>\) and
       the "title" command (C-a A).  The former can be output from an application to  control  the  window's
       name  under  software  control,  and the latter will prompt for a name when typed.  You can also bind
       pre-defined names to keys with the "title" command to set things quickly without prompting.

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

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

       Here's some .screenrc examples:

              screen -t top 2 nice top

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

                   shelltitle '> |csh'
                   screen 1

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

              /usr/joe/src/dir> trn

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

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

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

                   % !em
                   emacs file.c

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

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

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

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

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

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

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

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

       Each window in a screen session emulates a VT100 terminal, with some extra functions added. The VT100
       emulator is hard-coded, no other terminal types can be emulated.
       Usually screen tries to emulate as much of the VT100/ANSI standard as possible. But if your  terminal
       lacks  certain capabilities, the emulation may not be complete. In these cases screen has to tell the
       applications that some of the features are missing. This is no problem  on  machines  using  termcap,
       because screen can use the $TERMCAP variable to customize the standard screen termcap.

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

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

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

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

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

       Note that screen honors the "terminfo" .screenrc command if the system  uses  the  terminfo  database
       rather than termcap.

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

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

       Screen maintains a hardstatus line for every window. If a window gets selected, the  display's  hard-status hardstatus
       status  will  be  updated to match the window's hardstatus line. If the display has no hardstatus the
       line will be displayed as a standard screen message.  The hardstatus line can  be  changed  with  the
       ANSI  Application  Program  Command  (APC):  "ESC_<string>ESC\". As a convenience for xterm users the
       sequence "ESC]0..2;<string>^G" is also accepted.

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

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

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

       ESC E                      Next Line

       ESC D                      Index

       ESC M                      Reverse Index

       ESC H                      Horizontal Tab Set

       ESC Z                      Send VT100 Identification String

       ESC 7                 (V)  Save Cursor and Attributes

       ESC 8                 (V)  Restore Cursor and Attributes

       ESC [s                (A)  Save Cursor and Attributes

       ESC [u                (A)  Restore Cursor and Attributes

       ESC c                      Reset to Initial State

       ESC g                      Visual Bell

       ESC Pn p                   Cursor Visibility (97801)

           Pn = 6                 Invisible

                7                 Visible

       ESC =                 (V)  Application Keypad Mode

       ESC >                 (V)  Numeric Keypad Mode

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

       ESC \                 (A)  String Terminator

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

       ESC !                      Global Message String (Message Line)

       ESC k                      A.k.a. Definition String

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

       ESC _                 (A)  Application Program Command (Hardstatus)

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

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

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

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

       ESC n                 (A)  Lock Shift G2

       ESC o                 (A)  Lock Shift G3

       ESC N                 (A)  Single Shift G2

       ESC O                 (A)  Single Shift G3

       ESC ( Pcs             (A)  Designate character set as G0

       ESC ) Pcs             (A)  Designate character set as G1

       ESC * Pcs             (A)  Designate character set as G2

       ESC + Pcs             (A)  Designate character set as G3

       ESC [ Pn ; Pn H            Direct Cursor Addressing

       ESC [ Pn ; Pn f            same as above

       ESC [ Pn J                 Erase in Display

             Pn = None or 0       From Cursor to End of Screen

                  1               From Beginning of Screen to Cursor

                  2               Entire Screen

       ESC [ Pn K                 Erase in Line

             Pn = None or 0       From Cursor to End of Line

                  1               From Beginning of Line to Cursor

                  2               Entire Line

       ESC [ Pn X                 Erase character

       ESC [ Pn A                 Cursor Up

       ESC [ Pn B                 Cursor Down

       ESC [ Pn C                 Cursor Right

       ESC [ Pn D                 Cursor Left

       ESC [ Pn E                 Cursor next line

       ESC [ Pn F                 Cursor previous line

       ESC [ Pn G                 Cursor horizontal position

       ESC [ Pn `                 same as above

       ESC [ Pn d                 Cursor vertical position

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

             Ps = None or 0       Default Rendition

                  1               Bold

                  2          (A)  Faint

                  3          (A)  Standout Mode (ANSI: Italicized)

                  4               Underlined

                  5               Blinking

                  7               Negative Image

                  22         (A)  Normal Intensity

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

                  24         (A)  Not Underlined

                  25         (A)  Not Blinking

                  27         (A)  Positive Image

                  30         (A)  Foreground Black

                  31         (A)  Foreground Red

                  32         (A)  Foreground Green

                  33         (A)  Foreground Yellow

                  34         (A)  Foreground Blue

                  35         (A)  Foreground Magenta

                  36         (A)  Foreground Cyan

                  37         (A)  Foreground White

                  39         (A)  Foreground Default

                  40         (A)  Background Black


                  49         (A)  Background Default

       ESC [ Pn g                 Tab Clear

             Pn = None or 0       Clear Tab at Current Position

                  3               Clear All Tabs

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

       ESC [ Pn I            (A)  Horizontal Tab

       ESC [ Pn Z            (A)  Backward Tab

       ESC [ Pn L            (A)  Insert Line

       ESC [ Pn M            (A)  Delete Line

       ESC [ Pn @            (A)  Insert Character

       ESC [ Pn P            (A)  Delete Character

       ESC [ Pn S                 Scroll Scrolling Region Up

       ESC [ Pn T                 Scroll Scrolling Region Down

       ESC [ Pn ^                 same as above

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

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

             Ps = 4          (A)  Insert Mode

                  20         (A)  Automatic Linefeed Mode

                  34              Normal Cursor Visibility

                  ?1         (V)  Application Cursor Keys

                  ?3         (V)  Change Terminal Width to 132 columns

                  ?5         (V)  Reverse Video

                  ?6         (V)  Origin Mode

                  ?7         (V)  Wrap Mode

                  ?9              X10 mouse tracking

                  ?25        (V)  Visible Cursor

                  ?47             Alternate Screen (old xterm code)

                  ?1000      (V)  VT200 mouse tracking

                  ?1047           Alternate Screen (new xterm code)

                  ?1049           Alternate Screen (new xterm code)

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

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

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

       ESC [ c                    Send VT100 Identification String

       ESC [ x                    Send Terminal Parameter Report

       ESC [ > c                  Send VT220 Secondary Device Attributes String

       ESC [ 6 n                  Send Cursor Position Report

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

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

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

       The following table describes all terminal capabilities that are recognized by screen and are not  in
       the  termcap(5) manual.  You can place these capabilities in your termcap entries (in `/etc/termcap')
       or use them with the commands `termcap', `terminfo' and `termcapinfo' in your screenrc files.  It  is
       often not possible to place these capabilities in the terminfo database.

       LP   (bool)  Terminal  has  VT100 style margins (`magic margins'). Note that this capability is obso-lete obsolete
                    lete because screen uses the standard 'xn' instead.

       Z0   (str)   Change width to 132 columns.

       Z1   (str)   Change width to 80 columns.

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

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

       G0   (bool)  Terminal can deal with ISO 2022 font selection sequences.

       S0   (str)   Switch charset 'G0' to the specified charset. Default is '\E(%.'.

       E0   (str)   Switch charset 'G0' back to standard charset. Default is '\E(B'.

       C0   (str)   Use the string as a conversion table for font '0'. See  the  'ac'  capability  for  more

       CS   (str)   Switch cursor-keys to application mode.

       CE   (str)   Switch cursor-keys back to normal mode.

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

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

       KJ   (str)   Set the encoding of the terminal. See the 'encoding' command for valid encodings.

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

       AB   (str)   Same as 'AF', but change background color.

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

       XC   (str)   Describe a translation of characters to strings depending  on  the  current  font.  More
                    details follow in the next section.

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

       C8   (bool)  Terminal needs bold to display high-intensity colors (e.g. Eterm).

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

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

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

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

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

       Here is an example:

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

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

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

       This example shows one use of the extension:

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

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

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

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

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

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

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

       Ken Beal (,
       Rudolf Koenig (,
       Toerless Eckert (,
       Wayne Davison (,
       Patrick Wolfe (, kailand!pat),
       Bart Schaefer (,
       Nathan Glasser (,
       Larry W. Virden (,
       Howard Chu (,
       Tim MacKenzie (,
       Markku Jarvinen (mta@{cc,cs,ee},
       Marc Boucher (marc@CAM.ORG),
       Doug Siebert (,
       Ken Stillson (,
       Ian Frechett (frechett@spot.Colorado.EDU),
       Brian Koehmstedt (,
       Don Smith (,
       Frank van der Linden (,
       Martin Schweikert (,
       David Vrona (,
       E. Tye McQueen (,
       Matthew Green (,
       Christopher Williams (,
       Matt Mosley (,
       Gregory Neil Shapiro (gshapiro@wpi.WPI.EDU),
       Johannes Zellner (,
       Pablo Averbuj (

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

       The  latest official release of screen available via anonymous ftp from,
       or any other GNU distribution site. The home site of screen is, in the  directory
       pub/utilities/screen.  The  subdirectory  `private'  contains the latest beta testing release. If you
       want to help, send a note to

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

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

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

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

         Screen does not make use of hardware tabs.

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

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

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

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

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

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

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

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

         Send bug-reports, fixes, enhancements, t-shirts, money, beer & pizza to

4th Berkeley Distribution                         Aug 2003                                         SCREEN(1)

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