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.  Shells  usually  distinguish  between running as login-shell or
   sub-shell.  Screen runs them as sub-shells, unless told otherwise  (See
   "shell" .screenrc command).

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

   Screen  does  not  understand the prefix "C-" to mean control, although
   this notation is used in this manual for readability.  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. - Note that you cannot transport environment variables
   from the invoking shell  to  the  application  (emacs  in  this  case),
   because  it  is  forked  from  the  parent screen process, not from the
   invoking shell.

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


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

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

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


   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

   -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

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

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

   -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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   -p number_or_name|-|=|+
        Preselect  a window. This is useful when you want to reattach to a
        specific window or you want to send a command via the "-X"  option
        to a specific window. As with screen's select command, "-" selects
        the blank window. As a special case for reattach,  "="  brings  up
        the  windowlist on the blank window, while a "+" will create a new
        window. The command will not be executed if the  specified  window
        could not be found.

   -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.

   -Q   Some commands now can be queried from a remote session using  this
        flag,  e.g.  "screen  -Q  windows".  The  commands  will  send the
        response to the stdout of the querying process. If  there  was  an
        error  in  the command, then the querying process will exit with a
        non-zero status.

        The commands that can be queried now are:

   -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
        multiple  detached  screen  sessions.   The second form is used to
        connect to another user's screen session which runs  in  multiuser
        mode.  This  indicates  that  screen  should  look for sessions in
        another user's directory. This requires setuid-root.

   -R   resumes screen only when it's unambiguous  which  one  to  attach,
        usually   when  only  one  screen  is  detached.  Otherwise  lists
        available sessions.  -RR attempts to resume the youngest (in terms
        of   creation   time)   detached  screen  session  it  finds.   If
        successful, all other command-line options  are  ignored.   If  no
        detached  session exists, starts a new session using the specified
        options, just as if -R had not been specified. The option  is  set
        by default if screen is run as a login-shell (actually screen uses
        "-xRR" in that case).  For combinations with the -d/-D option  see
        there.  Note: Time-based session selection is a Debian addition.

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

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

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

   -T term
        Set the $TERM environment  varible  using  the  spcified  term  as
        opposed to the default setting of screen.

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

   -v   Print version number.

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

   -x   Attach  to  a  not  detached screen session. (Multi display mode).
        Screen refuses to attach from within itself.  But  when  cascading
        multiple screens, loops are not detected; take care.

   -X   Send  the  specified  command to a running screen session. You may
        use the -S option to  specify  the  screen  session  if  you  have
        several  screen  sessions running. 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.

   -4   Resolve hostnames only to IPv4 addresses.

   -6   Resolve hostnames only to IPv6 addresses.


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

   The following table shows the default key bindings:

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

   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.
                             See also split, remove, only.

   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

   C-a backspace
   C-a C-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.   See
                             also split, remove, focus.

   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 horizontally into
                             two new ones.  See also only, remove, focus.

   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.   See  also  split,
                             only, focus.

   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"

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

   C-a ?       (help)        Show key bindings.

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

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

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

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

   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

   C-a |       (split -v)    Split  the current region vertically into two
                             new ones.

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


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

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

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

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

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

   The following commands are available:

   acladd usernames [crypted-pw]
   addacl usernames

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

   aclchg usernames permbits list
   chacl usernames permbits list

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

   acldel username

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

   aclgrp username [groupname]

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

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

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

   activity message

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

               'Activity in window %n'

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

   allpartial on|off

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

   altscreen on|off

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

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

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

   attrcolor attrib [attribute/color-modifier]

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


          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

          attrcolor i "+b"

   Make bright colored text also bold.

   autodetach on|off

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

   autonuke on|off

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

   backtick id lifespan autorefresh cmd args
   backtick id

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

   bce [on|off]

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

   bell_msg [message]

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

               'Bell in window %n'

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

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

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

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

   Some examples:

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

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

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

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

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

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

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

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

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

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

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

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

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

   break [duration]

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


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

   blankerprg [program args]

   Defines  a  blanker  program.  Disables the blanker program if an empty
   argument is given. Shows  the  currently  set  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


   Swaps window with previous one on window list.


   Swaps window with next one on window list.

   c1 [on|off]

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

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

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

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

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

   charset set

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

   chdir [directory]

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

   cjkwidth [ on | off ]

   Treat ambiguous width characters as full/half width.


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


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

   colon [prefix]

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

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

   command [-c class]

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

   compacthist [on|off]

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

   console [on|off]

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


   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, C-h, or left arrow move the cursor left.
     j, C-n, or down arrow move the cursor down.
     k, C-p, or up arrow move the cursor up.
     l ('el') or right arrow move the cursor right.
     0 (zero) or C-a move to the leftmost column.
     + and - positions one line up and down.
     H,  M and L move the cursor to the leftmost column of the top, center
       or bottom line of the window.
     | moves to the specified absolute column.
     g or home moves to the beginning of the buffer.
     G or end moves to  the  specified  absolute  line  (default:  end  of
     % jumps to the specified percentage of the buffer.
     ^  or  $  move  to  the  leftmost  column,  to the first or last non-
       whitespace character on the line.
     w, b, and e move the cursor word by word.
     B, E move the cursor WORD by WORD (as in vi).
     f/F, t/T move the cursor forward/backward to the next  occurrence  of
       the  target.  (eg, '3fy' will move the cursor to the 3rd 'y' to the
     ; and  ,  Repeat  the  last  f/F/t/T  command  in  the  same/opposite
     C-e  and  C-y scroll the display up/down by one line while preserving
       the cursor position.
     C-u and C-d scroll the display up/down by  the  specified  amount  of
       lines  while preserving the cursor position. (Default: half screen-
     C-b and C-f scroll the display up/down a full screen.

       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 highlighted. Press:
     space  or  enter  to  set  the  first or second mark respectively. If
       mousetrack is set to `on', marks can also be set using  left  mouse
     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.
     n Find next search pattern.
     N Find previous search pattern.
       There  are  however  some keys that act differently than in vi.  Vi
       does not allow one to yank rectangular blocks of text,  but  screen
       does. Press:
     c  or  C  to  set the left or right margin respectively. If no repeat
       count is given, both default to the current cursor position.
       Example: Try this on a rather full text screen: "C-a [ M 20 l SPACE
       c 10 l 5 j C SPACE".

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

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

   copy_reg [key]

   No longer exists, use "readreg" instead.

   crlf [on|off]

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

   debug on|off

   Turns runtime debugging on or off. If screen  has  been  compiled  with
   option  -DDEBUG  debugging available and is turned on per default. Note
   that this command only affects debugging output from the main  "SCREEN"
   process  correctly.  Debug  output  from attacher processes can only be
   turned off once and forever.

   defc1 on|off

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

   defautonuke on|off

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

   defbce on|off

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

   defbreaktype [tcsendbreak|TIOCSBRK |TCSBRK]

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

   defcharset [set]

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

   defescape xy

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

   defflow on|off|auto [interrupt]

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

   defgr on|off

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

   defhstatus [status]

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

   defencoding enc

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

   deflog on|off

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

   deflogin on|off

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

   defmode mode

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

   defmonitor on|off

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

   defmousetrack on|off

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

   defnonblock on|off|numsecs

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

   defobuflimit limit

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

   defscrollback num

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

   defshell command

   Synonym to the shell .screenrc command. See there.

   defsilence on|off

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

   defslowpaste msec"

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

   defutf8 on|off

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

   defwrap on|off

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

   defwritelock on|off|auto

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

   defzombie [keys]

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

   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


   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.  The following
   keys can be used in displays list:
     k, C-p, or up Move up one line.
     j, C-n, or down Move down one line.
     C-a or home Move to the first line.
     C-e or end Move to the last line.
     C-u or C-d Move one half page up or down.
     C-b or C-f Move one full page up or down.
     mouseclick Move to the selected line. Available when "mousetrack"  is
       set to on.
     space Refresh the list
     d Detach that display
     D Power detach that display
     C-g, enter, or escape Exit the list

   The following is an example of what "displays" could look like:

          xterm 80x42 jnweiger@/dev/ttyp4     0(m11)   &rWx
          facit 80x24 mlschroe@/dev/ttyhf nb 11(tcsh)   rwx
          xterm 80x42 jnhollma@/dev/ttyp5     0(m11)   &R.x
           (A)   (B)     (C)     (D)     (E) (F)(G)   (H)(I)

   The legend is as follows:
   (A) The terminal type known by screen for this display.
   (B) Displays geometry as width x height.
   (C) Username who is logged in at the display.
   (D) Device name of the display or the attached device
   (E) Display is in blocking or nonblocking mode. The available modes are
   "nb", "NB", "Z<", "Z>", and "BL".
   (F) Number of the window
   (G) Name/title of window
   (H) Whether the window is shared
   (I) Window permissions. Made up of three characters:
         (1st character)
            '-' : no read
            'r' : read
            'R' : read only due to foreign wlock
         (2nd character)
            '-' : no write
            '.' : write suppressed by foreign wlock
            'w' : write
            'W' : own wlock
         (3rd character)
            '-' : no execute
            'x' : execute

   "Displays" needs a region size of at least 10  characters  wide  and  5
   characters high in order to display.

   digraph [preset[unicode-value]]

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


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

   echo [-n] message

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

   encoding enc [enc]

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

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

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

   escape xy

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

   eval command1 [command2 ]

   Parses and executes each argument as separate command.

   exec [[fdpat] newcommand [args ]]

   Run  a  unix subprocess (specified by an executable path newcommand and
   its optional arguments) in the current window. The flow of data between
   newcommands  stdin/stdout/stderr, the process originally started in the
   window  (let  us  call  it  "application-process")  and  screen  itself
   (window)  is  controlled  by  the  file descriptor pattern fdpat.  This
   pattern is basically a three  character  sequence  representing  stdin,
   stdout and stderr of newcommand. A dot (.) connects the file descriptor
   to screen.  An exclamation mark (!) causes the file  descriptor  to  be
   connected  to the application-process. A colon (:) combines both.  User
   input will go to newcommand unless newcommand receives the application-
   process' output (fdpats first character is `!' or `:') or a pipe symbol
   (|) is added (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 combinations. Each  drawing  shows  the
   digits 2,1,0 representing the three file descriptors of newcommand. The
   box marked `W' is the usual pty that has the application-process on its
   slave  side.   The  box  marked  `P'  is the secondary pty that now has
   screen at its master side.

   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 character (oct. 007) to  the  window  output
   seen  by screen.  This will cause "Bell in window x" messages, whenever
   the string "Error" appears in the window.


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

   flow [on|off|auto]

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

   focus [up|down|top|bottom]

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

   focusminsize [ ( width|max|_ ) ( height|max|_ ) ]

   This forces any currently selected region to be  automatically  resized
   at least a certain width and height. All other surrounding regions will
   be resized in order to accommodate.  This constraint follows  everytime
   the  "focus"  command  is  used.  The  "resize"  command can be used to
   increase either dimension of a region, but never below what is set with
   "focusminsize".  The  underscore  `_'  is  a synonym for max. Setting a
   width and height of `0 0' (zero zero) will  undo  any  constraints  and
   allow  for  manual resizing.  Without any parameters, the minimum width
   and height is shown.

   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.

   group [grouptitle]

   Change or show the group the current window belongs to. Windows can  be
   moved  around  between  different  groups by specifying the name of the
   destination group. Without specifying a group, the title of the current
   group is displayed.

   hardcopy [-h] [file]

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

   hardcopy_append on|off

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

   hardcopydir directory

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

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

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

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

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

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

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

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

   help [-c class]

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


   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

   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
   (or  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'. Without any options, the state of ignorecase is toggled.


   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

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

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

   The currently active character set (G0, G1, G2, or G3)  and  in  square
   brackets  the  terminal character sets that are currently designated as
   G0 through G3 is shown. If the window is  in  UTF-8  mode,  the  string
   "UTF-8" is shown instead.

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

   layout new [title]

   Create  a new layout. The screen will change to one whole region and be
   switched to the blank window. From here, you build the regions and  the
   windows  they  show as you desire. The new layout will be numbered with
   the smallest available integer, starting with zero. You can  optionally
   give  a  title  to  your new layout.  Otherwise, it will have a default
   title of "layout". You can always change the title later by  using  the
   command layout title.

   layout remove [n|title]

   Remove,  or  in  other  words,  delete the specified layout. Either the
   number or the title can be  specified.  Without  either  specification,
   screen will remove the current layout.

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

   layout next

   Switch to the next layout available

   layout prev

   Switch to the previous layout available

   layout select [n|title]

   Select  the  desired  layout.  Either  the  number  or the title can be
   specified. Without either specification, screen  will  prompt  and  ask
   which  screen  is  desired. To see which layouts are available, use the
   layout show command.

   layout show

   List on the message line the number(s) and title(s)  of  the  available
   layout(s). The current layout is flagged.

   layout title [title]

   Change  or display the title of the current layout. A string given will
   be used to name the layout. Without any options, the current title  and
   number is displayed on the message line.

   layout number [n]

   Change  or  display  the number of the current layout. An integer given
   will be used to number the layout. Without  any  options,  the  current
   number and title is displayed on the message line.

   layout attach [title|:last]

   Change  or  display  which  layout  to reattach back to. The default is
   :last, which tells screen to reattach back to the last used layout just
   before  detachment.  By  supplying  a title, You can instruct screen to
   reattach to a particular layout regardless which one was  used  at  the
   time of detachment. Without any options, the layout to reattach to will
   be shown in the message line.

   layout save [n|title]

   Remember the current arrangement of regions.  When  used,  screen  will
   remember  the arrangement of vertically and horizontally split regions.
   This arrangement is restored when a screen  session  is  reattached  or
   switched  back  from  a  different  layout.  If the session ends or the
   screen process dies, the layout arrangements are lost. The layout  dump
   command  should  help  in  this  siutation.  If  a  number  or title is
   supplied, screen will  remember  the  arrangement  of  that  particular
   layout. Without any options, screen will remember the current layout.

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

   layout autosave [on|off]

   Change or display  the  status  of  automatcally  saving  layouts.  The
   default  is  on,  meaning  when  screen  is  detached  or  changed to a
   different layout, the  arrangement  of  regions  and  windows  will  be
   remembered at the time of change and restored upon return.  If autosave
   is set to off, that arrangement will only be restored to either to  the
   last  manual  save,  using layout save, or to when the layout was first
   created, to a single region with a single window. Without either an  on
   or off, the current status is displayed on the message line.

   layout dump [filename]

   Write to a file the order of splits made in the current layout. This is
   useful to recreate the order of  your  regions  used  in  your  current
   layout.  Only  the  current  layout is recorded. While the order of the
   regions are recorded, the sizes of  those  regions  and  which  windows
   correspond  to  which regions are not. If no filename is specified, the
   default is layout-dump, saved in the directory that the screen  process
   was  started in. If the file already exists, layout dump will append to
   that file. As an example:

               C-a : layout dump /home/user/.screenrc

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


   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 `lockterminal'.

   log [on|off]

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

   logfile filename
   logfile flush secs

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

   login [on|off]

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

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

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


   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 [timeout]

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

   markkeys string

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

   maxwin num

   Set the maximum  window  number  screen  will  create.  Doesn't  affect
   already  existing  windows. The number can be increased only when there
   are no existing windows.


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

   monitor [on|off]

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

   mousetrack [on|off]

   This command determines whether screen will  watch  for  mouse  clicks.
   When  this  command is enabled, regions that have been split in various
   ways can be selected by pointing to them with a mouse and left-clicking
   them. Without specifying on or off, the current state is displayed. The
   default state is determined by the "defmousetrack" command.

   msgminwait sec

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

   msgwait sec

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

   multiuser on|off

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

   nethack on|off

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


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

   nonblock [on|off|numsecs]

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

   number [[+|-]n]

   Change the current window's number. If the given number  n  is  already
   used  by  another  window,  both  windows exchange their numbers. If no
   argument is specified, the current window number (and title) is  shown.
   Using `+' or `-' will change the window's number by the relative amount

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

   password [crypted_pw]

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

   paste [registers [dest_reg]]

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

   pastefont [on|off]

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


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


   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  keyboard.  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"


   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

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

   Change  the  way screen renders the titles of windows that have monitor
   or bell flags set in caption  or  hardstatus  or  windowlist.  See  the
   "STRING  ESCAPES" chapter for the syntax of the modifiers.  The default
   for monitor is currently "=b " (bold, active colors), for bell  "=ub  "
   (underline, bold and active colors), and "=u " for silence.


   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]|//group]

   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..MAXWIN-1 is
   given, the window number n is assigned to the newly created window (or,
   if  this  number  is  already in-use, the next available number).  If a
   command is specified after  "screen",  this  command  (with  the  given
   arguments) is started in the window; otherwise, a shell is created.  If
   //group is supplied, a container-type window is created in which  other
   windows may be created inside it.

   Thus, if your ".screenrc" contains the lines

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

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

   scrollback num

   Set  the  size  of the scrollback buffer for the current windows to num
   lines.  The  default  scrollback  is   100   lines.    See   also   the
   "defscrollback"  command and use "info" to view the current setting. To
   access and use the contents in the scrollback buffer,  use  the  "copy"

   select [WindowID]

   Switch to the window identified by WindowID.  This can be a prefix of a
   window title (alphanumeric  window  name)  or  a  window  number.   The
   parameter  is  optional  and  if  omitted,  you  get  prompted  for  an
   identifier.  When a new window  is  established,  the  first  available
   number  is  assigned  to  this  window.   Thus, the first window can be
   activated by "select 0".  The number of windows is limited at  compile-
   time  by  the  MAXWIN  configuration  parameter (which defaults to 40).
   There are two special WindowIDs, "-" selects the internal blank  window
   and  "."  selects the current window. The latter is useful if used with
   screen's "-X" option.

   sessionname [name]

   Rename the current session. Note, that  for  "screen  -list"  the  name
   shows  up  with  the  process-id  prepended.  If the argument "name" is
   omitted, the name of this  session  is  displayed.  Caution:  The  $STY
   environment  variables  will still reflect the old name in pre-existing
   shells. This may result in confusion. Use of this command is  generally
   discouraged. Use the "-S" command-line option if you want to name a new
   session.  The default is constructed from the tty and host names.

   setenv [var [string]]

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

   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

   shell command

   Set  the  command to be used to create a new shell.  This overrides the
   value of the environment variable $SHELL.  This is useful if you'd like
   to  run  a  tty-enhancer  which  is  expecting  to  execute the program
   specified in $SHELL.  If the command begins with a '-'  character,  the
   shell  will be started as a login-shell. Typical shells do only minimal
   initialization when not started as a login-shell.  E.g. Bash  will  not
   read your "~/.bashrc" unless it is 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.


   Sort the windows in alphabetical order of the window tiles.

   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]]

   This command is deprecated. See "rendition so" instead.

   split [-v]

   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. Splits are made horizontally unless -v  is
   used.  Use  the  "remove"  or the "only" command to delete regions. Use
   "focus" to toggle between regions.

   startup_message on|off

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

   stuff [string]

   Stuff  the  string  string  in  the input buffer of the current window.
   This is like the "paste" command but with much less overhead.   Without
   a  parameter,  screen  will  prompt  for a string to stuff.  You cannot
   paste large buffers with the "stuff" command. It is most useful for key
   bindings. See also "bindkey".

   su [username [password [password2]]]

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


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

   term term

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

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

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

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

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

   Some examples:

          termcap xterm*  LP:hs@

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

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

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

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

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

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

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

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

   time [string]

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

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

   title [windowtitle]

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


   Unbind  all the bindings. This can be useful when screen is used solely
   for its detaching abilities, such as when letting a console application
   run  as a daemon. If, for some reason, it is necessary to bind commands
   after this, use 'screen -X'.

   unsetenv var

   Unset an environment variable.

   utf8 [on|off [on|off]]

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

   vbell [on|off]

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

   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 a parameter, the current message is shown.

   vbellwait sec

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

   verbose [on|off]

   If verbose is switched on, the  command  name  is  echoed,  whenever  a
   window  is  created (or resurrected from zombie state). Default is off.
   Without a 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 specified.  This requires a capable  terminal
   and  the  termcap entries "Z0" and "Z1".  See the "termcap" command for
   more information. You can also specify a new  height  if  you  want  to
   change  both  values.   The -w option tells screen to leave the display
   size unchanged and just set the window size, -d vice versa.

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

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

   The following keys are used to navigate in "windowlist":
     k, C-p, or up Move up one line.
     j, C-n, or down Move down one line.
     C-g or escape Exit windowlist.
     C-a or home Move to the first line.
     C-e or end Move to the last line.
     C-u or C-d Move one half page up or down.
     C-b or C-f Move one full page up or down.
     0..9 Using the number keys, move to the selected line.
     mouseclick  Move to the selected line. Available when "mousetrack" is
       set to "on"
     / Search.
     n Repeat search in the forward direction.
     N Repeat search in the backward direction.
     m Toggle MRU.
     g Toggle group nesting.
     a All window view.
     C-h or backspace Back out the group.
     , Switch numbers with the previous window.
     . Switch numbers with the next window.
     K Kill that window.
     space or enter Select that window.

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

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

   windows [ string ]

   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.  The optional string parameter follows the "STRING  ESCAPES"
   format.   If  string parameter is passed, the output size is unlimited.
   The default command without any parameter is limited to a size of  1024

   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'. Without any options, the state of
   wrap is toggled.

   writebuf [-e encoding] [filename]

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

   writelock [on|off|auto]

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


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

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

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

   zombie [keys[onerror]]
   defzombie [keys]

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

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

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


   Per  default screen windows are removed from the window list as soon as
   the windows process (e.g. shell) exits.  If  zombie  keys  are  defined
   (compare  with  above  zombie  command),  it  is possible to also set a
   timeout when screen tries to  automatically  reconnect  a  dead  screen


   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
      consisting 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 -ixoff
             Enables  (or  disables)  software  flow-control for receiving

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

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

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

      When  the  CLOCAL status bit is true, the whole set of modem signals
      is placed inside curly braces  ({  and  }).   When  the  CRTSCTS  or
      TIOCSOFTCAR  bit  is  set,  the  signals  `CTS' or `CD' are shown in
      parenthesis, respectively.

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

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

      b      BINARY. The connection is in binary mode.

      e      ECHO. Local echo is disabled.

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

      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

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

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


   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

   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

   E      sets %? to true if the escape character has been pressed.

   f      flags  of  the window, see "windows" for meanings of the various

   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

   P      sets %? to true if the current region is in copy/paste mode

   S      session name

   s      seconds

   t      window title

   u      all other users on this window

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

   W      all window numbers and names except the current one

   x      the executed command including arguments running in this windows

   X      the executed command without arguments running in this windows

   y      last two digits of the year number

   Y      full year number

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

   :      else part of '%?'

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

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

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

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

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

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

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

   +      add the specified set to the current attributes

   -      remove the set from the current attributes

   !      invert the set in the current attributes

   =      change the current attributes to the specified set

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

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

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

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

   The  capitalized  versions of the letter specify bright colors. You can
   also use the pseudo-color 'i' to set just the brightness and leave  the
   color unchanged.
   A  one  digit/letter  color  description  is  treated  as foreground or
   background color dependent 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 behavior for two-letter color descriptions, also prefix
   them with a ".".
   As a special case, "%{-}" restores the attributes and colors that  were
   set before the last change was made (i.e., pops one level of the color-
   change stack).


   "G"    set color to bright green

   "+b r" use bold red

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

   %-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

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


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

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

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

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

TITLES (naming windows)

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

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

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

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

   Here's some .screenrc examples:

          screen -t top 2 nice top

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

               shelltitle '> |csh'
               screen 1

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

          /usr/joe/src/dir> trn

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

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

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

               % !em
               emacs file.c

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

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

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

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

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

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

          PROMPT_COMMAND='printf "\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 window.

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

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

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

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

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

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

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

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

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

   ESC E                      Next Line

   ESC D                      Index

   ESC M                      Reverse Index

   ESC H                      Horizontal Tab Set

   ESC Z                      Send VT100 Identification String

   ESC 7                 (V)  Save Cursor and Attributes

   ESC 8                 (V)  Restore Cursor and Attributes

   ESC [s                (A)  Save Cursor and Attributes

   ESC [u                (A)  Restore Cursor and Attributes

   ESC c                      Reset to Initial State

   ESC g                      Visual Bell

   ESC Pn p                   Cursor Visibility (97801)

       Pn = 6                 Invisible

            7                 Visible

   ESC =                 (V)  Application Keypad Mode

   ESC >                 (V)  Numeric Keypad Mode

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

   ESC \                 (A)  String Terminator

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

   ESC !                      Global Message String (Message Line)

   ESC k                      A.k.a. Definition String

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

   ESC _                 (A)  Application Program Command (Hardstatus)

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

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

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

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

   ESC n                 (A)  Lock Shift G2

   ESC o                 (A)  Lock Shift G3

   ESC N                 (A)  Single Shift G2

   ESC O                 (A)  Single Shift G3

   ESC ( Pcs             (A)  Designate character set as G0

   ESC ) Pcs             (A)  Designate character set as G1

   ESC * Pcs             (A)  Designate character set as G2

   ESC + Pcs             (A)  Designate character set as G3

   ESC [ Pn ; Pn H            Direct Cursor Addressing

   ESC [ Pn ; Pn f            same as above

   ESC [ Pn J                 Erase in Display

         Pn = None or 0       From Cursor to End of Screen

              1               From Beginning of Screen to Cursor

              2               Entire Screen

   ESC [ Pn K                 Erase in Line

         Pn = None or 0       From Cursor to End of Line

              1               From Beginning of Line to Cursor

              2               Entire Line

   ESC [ Pn X                 Erase character

   ESC [ Pn A                 Cursor Up

   ESC [ Pn B                 Cursor Down

   ESC [ Pn C                 Cursor Right

   ESC [ Pn D                 Cursor Left

   ESC [ Pn E                 Cursor next line

   ESC [ Pn F                 Cursor previous line

   ESC [ Pn G                 Cursor horizontal position

   ESC [ Pn `                 same as above

   ESC [ Pn d                 Cursor vertical position

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

         Ps = None or 0       Default Rendition

              1               Bold

              2          (A)  Faint

              3          (A)  Standout Mode (ANSI: Italicized)

              4               Underlined

              5               Blinking

              7               Negative Image

              22         (A)  Normal Intensity

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

              24         (A)  Not Underlined

              25         (A)  Not Blinking

              27         (A)  Positive Image

              30         (A)  Foreground Black

              31         (A)  Foreground Red

              32         (A)  Foreground Green

              33         (A)  Foreground Yellow

              34         (A)  Foreground Blue

              35         (A)  Foreground Magenta

              36         (A)  Foreground Cyan

              37         (A)  Foreground White

              39         (A)  Foreground Default

              40         (A)  Background Black

              ...               ...

              49         (A)  Background Default

   ESC [ Pn g                 Tab Clear

         Pn = None or 0       Clear Tab at Current Position

              3               Clear All Tabs

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

   ESC [ Pn I            (A)  Horizontal Tab

   ESC [ Pn Z            (A)  Backward Tab

   ESC [ Pn L            (A)  Insert Line

   ESC [ Pn M            (A)  Delete Line

   ESC [ Pn @            (A)  Insert Character

   ESC [ Pn P            (A)  Delete Character

   ESC [ Pn S                 Scroll Scrolling Region Up

   ESC [ Pn T                 Scroll Scrolling Region Down

   ESC [ Pn ^                 same as above

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

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

         Ps = 4          (A)  Insert Mode

              20         (A)  Automatic Linefeed Mode

              34              Normal Cursor Visibility

              ?1         (V)  Application Cursor Keys

              ?3         (V)  Change Terminal Width to 132 columns

              ?5         (V)  Reverse Video

              ?6         (V)  Origin Mode

              ?7         (V)  Wrap Mode

              ?9              X10 mouse tracking

              ?25        (V)  Visible Cursor

              ?47             Alternate Screen (old xterm code)

              ?1000      (V)  VT200 mouse tracking

              ?1047           Alternate Screen (new xterm code)

              ?1049           Alternate Screen (new xterm code)

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

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

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

   ESC [ c                    Send VT100 Identification String

   ESC [ x                    Send Terminal Parameter Report

   ESC [ > c                  Send   VT220   Secondary  Device  Attributes

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

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

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


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

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

   Z0   (str)   Change width to 132 columns.

   Z1   (str)   Change width to 80 columns.

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

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

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

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

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

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

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

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

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

   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  /

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

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

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

   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 characters '\', '%', and ','.

   Here is an example:

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

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

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

   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
   HOME           Directory in which to look for .screenrc.
   LINES          Number of  lines  on  the  terminal  (overrides  termcap
   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").  See also "shell" .screenrc command.
   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.
   /etc/screenrc                     screen initialization commands
   $HOME/.screenrc                   Read in after /etc/screenrc
   /var/run/screen/S-<login>         Socket directories (default)
   /usr/tmp/screens/S-<login>        Alternate socket directories.
   <socket directory>/.termcap       Written  by  the   "termcap"   output
   /usr/tmp/screens/screen-exchange  or
   /tmp/screen-exchange              screen   `interprocess  communication
   hardcopy.[0-9]                    Screen images created by the hardcopy
   screenlog.[0-9]                   Output  log  files created by the log
   /usr/lib/terminfo/?/*             or
   /etc/termcap                      Terminal capability databases
   /var/run/utmp                     Login records
   $LOCKPRG                          Program that locks a terminal.


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


   Originally created by Oliver Laumann. For a long  time  maintained  and
   developed by Juergen Weigert, Michael Schroeder, Micah Cowan and Sadrul
   Habib Chowdhury. This latest version was produced by Amadeusz Sawiski
   <>            and            Alexander           Naumov


   Copyright (c) 2010-2015
        Juergen Weigert (
        Sadrul Habib Chowdhury (
   Copyright (c) 2008, 2009
        Juergen Weigert (
        Michael Schroeder (
        Micah Cowan (
        Sadrul Habib Chowdhury (
   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 3, 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
   General Public License for more details.
   You should have received a copy of the GNU General Public License along
   with  this  program  (see  the file COPYING); if not, write to the Free
   Software Foundation, Inc., 59 Temple Place  -  Suite  330,  Boston,  MA
   02111-1307, USA


   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 (


   The  latest official release of screen available via anonymous ftp from or any other GNU distribution  site.  The  home
   site  of  screen  is 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 correctly change the owner of the tty device
      file for each window.  Special permission may also  be  required  to
      write the file "/var/run/utmp".

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

   *  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

   *  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 personal 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

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


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