screen - screen manager with VT100/ANSI terminal emulation


SYNOPSIS

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


DESCRIPTION

       Screen is a full-screen window manager that multiplexes  a
       physical  terminal  between  several  processes (typically
       interactive shells).  Each virtual terminal  provides  the
       functions  of  a DEC VT100 terminal and, in addition, sev­
       eral control functions from the ISO 6492  (ECMA  48,  ANSI
       X3.64) and ISO 2022 standards (e.g. insert/delete line and
       support for multiple character sets).  There is a  scroll­
       back  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 nor­
       mally 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  win­
       dows,  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 win­
       dows run their programs  completely  independent  of  each
       other.  Programs continue to run when their window is cur­
       rently not visible and even when the whole screen  session
       is detached from the user's terminal.  When a program ter­
       minates, screen (per default) kills the window  that  con­
       tained it.  If this window was in the foreground, the dis­
       play switches to the previous window; if  none  are  left,
       screen exits.

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

       Screen does not understand the prefix "C-"  to  mean  con­
       trol.   Please use the caret notation ("^A" instead of "C-
       a") as arguments to e.g. the  escape  command  or  the  -e

       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.  Simi­
       larly, you can create a new window with a  custom  command
       in it by first binding the command to a keystroke (in your
       .screenrc file or at the "C-a :" command  line)  and  then
       using  it just like the "C-a c" command.  In addition, new
       windows can be created by running a command like:

              screen emacs prog.c

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

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


GETTING STARTED

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

       If you're impatient and want to get started without  doing
       a  lot more reading, you should remember this one command:
       "C-a ?".  Typing these two characters will display a  list
       of  the available screen commands and their bindings. Each
       keystroke is discussed in the section "DEFAULT  KEY  BIND­
       INGS".  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  to  use  a
       version of your terminal's termcap that has automatic mar­
       gins turned off. This will ensure an accurate and  optimal
       update  of the screen in all circumstances. Most terminals

       usable last column). This is the VT100 style type and per­
       fectly suited for screen.  If all you've got is  a  "true"
       auto-margin terminal screen will be content to use it, but
       updating a character put into the  last  position  on  the
       screen may not be possible until the screen scrolls or the
       character is moved into a safe position in some other way.
       This  delay  can  be  shortened  by  using a terminal with
       insert-character capability.


COMMAND-LINE OPTIONS

       Screen has the following command-line options:

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

       -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 resiz­
            able terminals (those with "WS" in  its  description,
            e.g. suncmd or some xterm).

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

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

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

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

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

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

       -D -R   Attach  here  and  now. In detail this means: If a
               session is running, then  reattach.  If  necessary

               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 char­
            acter 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 com­
            mand character. But when attaching to an already run­
            ning  session,  this  option changes only the command
            character of the  attaching  user.   This  option  is
            equivalent  to  either  the  commands  "defescape" or
            "escape" respectively.

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

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

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

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

       -ls and -list
            does  not  start  screen,  but  prints  a   list   of
            pid.tty.host  strings  identifying  your  screen ses­
            sions.  Sessions marked  `detached'  can  be  resumed
            with "screen -r". Those marked `attached' are running
            and have a controlling terminal. If the session  runs
            in  multiuser  mode,  it  is marked `multi'. Sessions
            marked as `unreachable' either live  on  a  different
            host  or  are `dead'.  An unreachable session is con­
            sidered dead, when its name matches either  the  name
            of  the  local  host,  or the specified parameter, if

            struct  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 your auto-margin terminal has a writable
            last-position on the screen.  This can also be set in
            your .screenrc by specifying `LP' in a "termcap" com­
            mand.

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

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

       -m -D   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.

       -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 direc­
            tory with running but not attachable sessions. 11 (or
            more) indicates 1 (or more) usable sessions.  In com­
            bination with "-r" the exit value is as  follows:  10
            indicates  that there is no session to resume. 12 (or
            more) indicates that there are 2 (or  more)  sessions
            to resume and you should specify which one to choose.
            In all other cases "-q" has no effect.

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

            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.
            For combinations with the -d/-D option see there.

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

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

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

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

       -v   Print version number.

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

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

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


DEFAULT KEY BINDINGS

       As mentioned, each screen command consists of a "C-a" fol­
       lowed  by  one other character.  For your convenience, all

       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 '
       C-a "       (select)      Prompt for a window name or num­
                                 ber to switch to.

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

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

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

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

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

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

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

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

       C-a C       (clear)       Clear the screen.

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

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

       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  cur­
                                 rent window to the file "screen­
                                 log.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 con­
                                 figured  to  update   the   utmp
                                 database.

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

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

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

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

       C-a backspace
       C-a 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.

                                 rent one.

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

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

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

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

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

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

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

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

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

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

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

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

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

       C-a ?       (help)        Show key bindings.

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

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

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

                                 buffer to the stdin queue of the
                                 current window.

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

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

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

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

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

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

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


CUSTOMIZATION

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

       When screen is invoked, it  executes  initialization  com­
       mands  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 envi­
       ronment  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.

       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 pre­
       vious 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 com­
       mands.

       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 cur­
       rent settings.

       The following commands are available:

       acladd usernames [crypted-pw]
       addacl usernames

       Enable  users  to  fully access this screen session. User­
       names 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'.  Pre­
       fixing  `+'  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  com­
       mands.  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 cur­
       rently 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

       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  cur­
       rently 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 parame­
       ter 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 con­
       trol 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'

       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 win­
       dows.

       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 com­
       mand.  If  the first parameter describes a non-unique con­
       text, the command will be executed multiple times. If  the
       first  parameter is of the form `identifier*' then identi­
       fier is matched against user names.  The command  is  exe­
       cuted  once  for  each display of the selected user(s). If
       the first parameter is of the form  `identifier%'  identi­
       fier 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  win­
       dows 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 exe­
       cuted 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.
       "stuff",  "process"  or "paste") 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

       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.

       Examples:

              attrcolor b "R"

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

              attrcolor u "-u b"

       Use blue text instead of underline

              attrcolor b "I"

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

       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".

       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  num­
       ber  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


       An empty message can be supplied to the "bell_msg" command
       to suppress output of a message line (bell_msg "").  With­
       out parameter, the current message is shown.

       bind 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 indi­
       cated in the "DEFAULT KEY BINDINGS" section, e.g. the com­
       mand  to  create  a  new window is bound to "C-c" and "c".
       The "bind" command can be used to redefine the  key  bind­
       ings  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.

       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 com­
       mand. 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.

       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 pro­
       grammed by the user, one for the default actions used  for
       terminal  emulation  and  one for screen's copy mode to do
       cursor movement. See section  "INPUT  TRANSLATION"  for  a
       list of default key bindings.
       If  the  -d  option is given, bindkey modifies the default

       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  tim­
       ing.  One cannot turn off the timing if a termcap capabil­
       ity is used.
       Cmd can be any of screen's commands with an arbitrary num­
       ber 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 win­
       dow.  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  pro­
       cess  (See also chapter "WINDOW TYPES"). The maximum dura­
       tion of a break signal is limited to 15 seconds.

       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

       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  "buffer­
       file"    command   is   omitted,   the   default   setting
       ("/tmp/screen-exchange") is  reactivated.   The  following
       example  will  paste  the  system's password file into the
       screen window  (using  the  paste  buffer,  where  a  copy
       remains):

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

       c1 [on|off]

       Change  c1  code processing. "C1 on" tells screen to treat
       the input characters between 128 and 159 as control  func­
       tions.   Such  an  8-bit  code is normally the same as ESC
       followed by the corresponding 7-bit code. The default set­
       ting  is  to  process c1 codes and can be changed with the
       "defc1" command.  Users with fonts that have usable  char­
       acters 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 addi­
       tional 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

       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" com­
       mand  from within ".screenrc" or by means of "C-a : screen
       ..." or "C-a c"  use  this  as  their  default  directory.
       Without  a chdir command, this would be the directory from
       which screen was invoked.   Hardcopy  and  log  files  are
       always  written to the window's default directory, not the
       current directory of the process running  in  the  window.
       You  can use this command multiple times in your .screenrc
       to start various windows in different default directories,
       but  the  last chdir value will affect all the windows you
       create interactively.

       clear

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

       colon [prefix]

       Allows  you to enter ".screenrc" command lines. Useful for
       on-the-fly modification of key bindings,  specific  window
       creation  and  changing settings. Note that the "set" key­
       word 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

       This command has the same  effect  as  typing  the  screen
       escape  character (^A). It is probably only useful for key
       bindings.  See also "bindkey".

       compacthist [on|off]

       This tells screen weather 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


       copy

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

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

       Marking:
           The copy range is specified by setting two marks.  The
           text between these marks will be highlighted. Press
         space to set the first or second mark respectively.
         Y  and  y  used  to  mark one whole line or to mark from
           start of line.
         W marks exactly one word.
       Repeat count:
           Any of these commands can be prefixed  with  a  repeat
           count number by pressing digits
         0..9 which is taken as a repeat count.
           Example: "C-a C-[ H 10 j 5 Y" will copy lines 11 to 15
           into the paste buffer.
       Searching:
         / Vi-like search forward.
         ? Vi-like search backward.
         C-a s Emacs style incremental search forward.
         C-r Emacs style reverse i-search.
       Specials:
           There are however some keys that act differently  than
           in  vi.   Vi  does  not  allow one to yank rectangular

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

       copy_reg [key]

       No longer exists, use "readreg" instead.

       crlf [on|off]

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


       Turns runtime debugging on or off. If screen has been com­
       piled 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 set­
       ting 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  termi­
       nal 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.   Tcsend­
       break and TIOCSBRK may or may not produce long breaks with
       spikes (e.g. 4 per second). This is not only system depen­
       dant,  this  also  differs  between  serial board drivers.
       Calling "defbreaktype" with no parameter displays the cur­
       rent 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.


       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 cur­
       rent default string is displayed.  Per default  the  hard­
       status line of new windows is empty.

       defkanji jis|sjis|euc

       Same  as the kanji command except that the default setting
       for new windows is changed. Initial setting is `off', i.e.
       `jis'.

       deflogin on|off

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

       defmode mode

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

       defmonitor on|off

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

       defobuflimit limit

       Same as the obuflimit command except that the default set­
       ting 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


       defscrollback num

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

       defshell command

       Synonym to the shell command. See there.

       defsilence on|off

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

       defslowpaste msec"

       Same as the slowpaste command except that the default set­
       ting for new windows is changed. Initial setting is 0 mil­
       liseconds, 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 set­
       ting for new windows is changed. Initially writelocks will
       off.

       defzombie [keys]

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

       detach

       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".)


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

       displays

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

       digraph [preset]

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

       dumptermcap

       Write the termcap entry for the virtual terminal optimized
       for the currently active window to the file ".termcap"  in
       the  user's  "$HOME/.screen" directory (or wherever screen
       stores its sockets. See the "FILES" section below).   This
       termcap entry is identical to the value of the environment
       variable $TERMCAP that is set up by screen for  each  win­
       dow.  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.

       escape xy

       Set  the command character to x and the character generat­
       ing 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 "\\".  The default is "^Aa".

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

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

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

       Examples:

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

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

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

       operates on stdout, then add another `!'.

              exec !..| less
              |less

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

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

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

       fit

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

       flow [on|off|auto]

       Sets  the  flow-control  mode  for  this  window.  Without
       parameters it cycles  the  current  window's  flow-control
       setting  from  "automatic" to "on" to "off".  See the dis­
       cussion 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 `bot­
       tom' go to the top and bottom region respectively.  Useful
       bindings are (j and k as in vi)
           bind j focus down
           bind k focus up
           bind t focus top
           bind b focus bottom

       gr [on|off]

       Turn  GR charset switching on/off. Whenever screen sees an

       charset stored in the GR slot and print the character with
       the 8th bit stripped. The default (see  also  "defgr")  is
       not to process GR switching because otherwise the ISO88591
       charset would not work.

       hardcopy

       Writes out the currently displayed image to a  file  hard­
       copy.n  in  the window's default directory, where n is the
       number of the current  window.   This  either  appends  or
       overwrites the file if it exists. See below.

       hardcopy_append on|off

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

       hardcopydir directory

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

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

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

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

       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

       Not really a online help, but displays a help screen show­
       ing 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.  See also "DEFAULT KEY BINDINGS" section.

       history

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

       hstatus status

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

       info

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

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


       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, insert mode, origin mode, application-key­
       pad mode, output logging, activity monitoring  or  partial
       redraw enabled.

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

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

       ins_reg [key]

       No longer exists, use "paste" instead.

       kanji jis|euc|sjis [jis|euc|sjis]

       Tell  screen  how to process kanji input/output. The first
       argument sets the kanji type of the current  window.  Each
       window  can  emulate a different type. The optional second
       parameter tells screen how to write the kanji codes to the
       connected  terminal.  The  preferred method of setting the
       display type is to use the "KJ" termcap entry.   See  also
       "defkanji",  which  changes  the  default setting of a new
       window.

       kill

       Kill current window.
       If there is an `exec' command running then it  is  killed.
       Otherwise  the  process  (shell)  running  in  the  window
       receives a  HANGUP  condition,  the  window  structure  is
       removed and screen (your display) switches to another win­
       dow.  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 com­
       mands "msgwait" and "msgminwait" for fine tuning.

       license

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

       lockscreen

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

       log [on|off]

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

       logfile filename
       logfile flush secs

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

       login [on|off]

       Adds or removes the entry in the utmp  database  file  for
       the  current  window.   This  controls  if  the  window is

       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  con­
       fig.h.in)  should  be  "on"  for  a screen that runs under
       suid-root.  Use  the  "deflogin"  command  to  change  the
       default  login  state  for  new windows. Both commands are
       only present when screen has been compiled with utmp  sup­
       port.

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

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

       mapdefault

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

       mapnotnext

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

       maptimeout [timo]

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

       markkeys string

       This is a method of changing the keymap used for copy/his­
       tory 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

       by  binding  these  characters  to  do nothing.  The no-op
       character is `@' and is used like this:  "markkeys  @=L=H"
       if  you  do  not  want  to use the `H' or `L' commands any
       longer.  As shown in this example, multiple  keys  can  be
       assigned to one function in a single statement.

       meta

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

       monitor [on|off]

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

       msgminwait sec

       Defines the time screen delays a new message when one mes­
       sage 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 com­
       mands `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.


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

       nonblock [on|off]

       Enable or disable flow control for the current user inter­
       face (display).  It is used to prevent a slow display from
       slowing down the processing of data output  by  a  window.
       This  command  may  be helpful when multiple displays show
       the same window. Nonblock is initially off  for  all  dis­
       plays.

       number [n]

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

       obuflimit [limit]

       If the output buffer contains more bytes than  the  speci­
       fied  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 argu­
       ment is specified, the current setting is displayed.

       only

       Kill all regions but the current one.

       other

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

       partial on|off

       Defines  whether  the display should be refreshed (as with
       redisplay) after switching to  the  current  window.  This
       command  only  affects the current window.  To immediately
       affect all windows use the allpartial command.  Default is
       `off', of course.  This default is fixed, as there is cur­
       rently 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

       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  check­
       ing.

       paste [registers [dest_reg]]

       Write  the (concatenated) contents of the specified regis­
       ters to the stdin queue of the current window. The  regis­
       ter '.' 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 reg­
       isters  is  pasted  into  the  named  destination register
       rather than the window. If '.' is used as the second argu­
       ment, 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 espe­
       cially useful for multi character fonts like kanji.

       pow_break

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

       pow_detach

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

       pow_detach_msg [message]

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

       prev

       Switch to the window with the  next  lower  number.   This

       of windows.

       printcmd [cmd]

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

       process [key]

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

       quit

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

       readbuf [filename]

       Reads  the  contents  of the specified file into the paste
       buffer.  If no  file  is  specified,  the  screen-exchange
       filename is used.  See also "bufferfile" command.

       readreg [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.  The  fol­
       lowing  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 redis­
       play when in partial redraw mode.

       register key string

       Save the specified string to the register  key.  See  also
       the "paste" command.

       remove

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

       removebuf

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

       reset

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

       resize

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

              resize +N   increase current region height by N

              resize -N   decrease current region height by N

              resize  N   set current region height to N

              resize  =   make all windows equally high

              resize  max maximize current region height

              resize  min minimize current region height

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

       Establish a new window.  The flow-control options (-f, -fn
       and -fa), title (a.k.a.) option (-t),  login  options  (-l
       and -ln) , terminal type option (-T <term>), the all-capa­
       bility-flag (-a) and scrollback option (-h <num>)  may  be
       specified  with each command.  The option (-M) turns moni­
       toring on for this window.  The option (-L)  turns  output
       logging  on  for  this window.  If an optional number n in

       to the newly created window (or, if this number is already
       in-use, the next available number).  If a command is spec­
       ified  after  "screen", this command (with the given argu­
       ments) is started in the window;  otherwise,  a  shell  is
       created.  Thus, if your ".screenrc" contains the lines

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

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

       scrollback num

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

       select [WindowID]

       Switch to the window identified by WindowID.  This can  be
       a prefix of a window title (alphanumeric window name) or a
       window number.  The parameter is optional and if  omitted,
       you  get prompted for an identifier.  When a new window is
       established, the first available  number  is  assigned  to
       this  window.   Thus, the first window can be activated by
       "select 0".  The number of windows is limited at  compile-
       time by the MAXWIN configuration parameter.

       sessionname [name]

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

       setenv [var [string]]

       Set the environment variable var to value string.  If only

       value.  If no parameters are specified, the user  will  be
       prompted  for  both variable and value. The environment is
       inherited by all subsequently forked shells.

       shell command

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

       shelltitle title

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

       silence [on|off|sec]

       Toggles  silence  monitoring  of windows.  When silence is
       turned on and an affected  window  is  switched  into  the
       background, you will receive the silence notification mes­
       sage in the status line after a specified period of  inac­
       tivity  (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 sec­
       onds.

       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 cur­
       rent window by the paste ("C-a ]") command.  If the  slow­
       paste  value is nonzero text is written character by char­
       acter.  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  underly­
       ing  system  exposes  flow  control problems while pasting
       large amounts of text.


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

       split

       Split the current region into two new ones. All regions on
       the display are resized to make room for the  new  region.
       The blank window is displayed on the new region.

       startup_message on|off

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

       stuff string

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

       su [username [password [password2]]

       Substitute the user of a display. The command prompts  for
       all  parameters  that are omitted. If passwords are speci­
       fied 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 administra­
       tor  to  test  multiuser  setups.  When the identification
       fails, the user has access to the commands  available  for
       user  nobody.   These  are "detach", "license", "version",
       "help" and "displays".

       suspend

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

       term term

       In each window's environment screen opens, the $TERM vari­
       able  is set to "screen" by default.  But when no descrip­
       tion 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-

       $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  cus­
       tomize the termcap generated for the windows.  You have to
       place these commands in one of the screenrc startup files,
       as  they  are  meaningless  once  the terminal emulator is
       booted.
       If your system works uses  the  terminfo  database  rather
       than  termcap,  screen will understand the `terminfo' com­
       mand, 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 ter­
       minfo and termcap syntax, you can use the  command  `term­
       capinfo',  which  is just a shorthand for a pair of `term­
       cap' 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 TER­
       MINAL" 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).

       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 termi­
       nals 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 "VIR­
       TUAL TERMINAL" in this manual, and the termcap(5) man page
       for more information on termcap definitions.

       time

       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".

       title [windowalias]

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


       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' (ter­
       minfo: 'flash').
       Per default, vbell is off, thus the audible bell is  used.
       See also `bell_msg'.

       vbell_msg [message]

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

       vbellwait sec

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

       verbose [on|off]

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

       version

       Print the current version and the compile date in the sta­
       tus line.

       wall message

       Write a message to all displays. The message  will  appear


       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 dis­
       play  size unchanged and just set the window size, -d vice
       versa.

       windows

       Uses the message line to display a list of  all  the  win­
       dows.   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 pre­
       vious 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  back­
       ground window that is being monitored and has had activity
       occur is marked with an `@'; a  window  which  has  output
       logging  turned  on is marked with `(L)'; windows occupied
       by other users are marked with `&'; windows in the  zombie
       state  are  marked  with `Z'.  If this list is too long to
       fit on the terminal's status line only the portion  around
       the current window is displayed.

       wrap [on|off]

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

       writebuf [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.
       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

       may obtain the writelock (automatically). The writelock of
       the  current  window is disabled by the command "writelock
       off". If the user issues the  command  "writelock  on"  he
       keeps  the  exclusive  write permission while switching to
       other windows.

       xoff
       xon

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

       zombie [keys]
       defzombie [keys]

       Per  default  screen  windows  are removed from the window
       list as soon as the windows process  (e.g.  shell)  exits.
       When  a string of two keys is specified to the zombie com­
       mand, `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 win­
       dows disappear when their process exits.

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


THE MESSAGE LINE

       Screen displays informational messages and other  diagnos­
       tics 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, other­
       wise 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 sec­
       onds 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  '$WIN­
              DOW'<esc>\\'

       '\\' turns into a single backslash.


WINDOW TYPES

       Screen  provides three different window types. New windows
       are created with screen's screen  command  (see  also  the
       entry  in chapter "CUSTOMIZATION"). The first parameter to
       the screen command defines which type of  window  is  cre­
       ated.  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):

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

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

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

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

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

          You  may  want  to  specify as many of these options as
          applicable.  Unspecified  options  cause  the  terminal
          driver  to  make up the parameter values of the connec­
          tion.  These values are system dependant and may be  in


          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 capabili­
          ties 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 param­
          eter  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  com­
          municate with that server.
          For  telnet  windows,  the  command  info shows details
          about the connection in square brackets ([  and  ])  at
          the end of the status line.

          b      BINARY. The connection is in binary mode.

          e      ECHO. Local echo is disabled.

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

          t      TTYPE. The terminal type has been  requested  by
                 the remote host.  Screen sends the name "screen"
                 unless instructed otherwise (see also  the  com­
                 mand `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


          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 com­
          piled with the BUILTIN_TELNET option defined.


STRING ESCAPES

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

       Here is the full list of supported escapes:

       %      the escape character itself

       a      either 'am' or 'pm'

       A      either 'AM' or 'PM'

       c      current time HH:MM in 24h format

       C      current time HH:MM in 12h format

       d      day number

       D      weekday name

       h      hardstatus of the window

       l      current load of the system

       m      month number

       M      month name

       n      window number

       s      seconds

       t      window title

       u      all other users on this window

       w      all window numbers and names

       W      all window numbers and names except the current one

       y      last two digits of the year number


       ?      the part to the next '%?' is displayed only  if  an
              escape expands to an nonempty string

       :      else part of '%?'

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

       The 'c' and 'C' escape may be qualified with a '0' to make
       screen  use  zero  instead of space as fill character. The
       'n' escape understands a length qualifier (e.g. '%3n').

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

       +      add the specified set to the current attributes

       -      remove the set from the current attributes

       !      invert the set in the current attributes

       =      change the current attributes to the specified set

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

       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

       the brightness and leave the color unchanged.
       A one digit/letter color description is treated  as  fore­
       ground  or  background  color  dependant  on  the  current
       attributes: if reverse mode is set, the  background  color
       is  changed instead of the foreground color.  If you don't
       like this, prefix the color with a ".". If  you  want  the
       same  behaviour  for  two-letter  color descriptions, also
       prefix them with a ".".

       Examples:

       "G"    set color to bright green

       "+b r" use bold red

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


FLOW-CONTROL

       Each window has a flow-control setting that determines how
       screen deals with the XON and XOFF characters (and perhaps
       the  interrupt  character).   When  flow-control is turned
       off, screen ignores the XON  and  XOFF  characters,  which
       allows  the  user  to  send them to the current program by
       simply typing them  (useful  for  the  emacs  editor,  for
       instance).   The trade-off is that it will take longer for
       output from a "normal" program to pause in response to  an
       XOFF.   With  flow-control turned on, XON and XOFF charac­
       ters are used to immediately pause the output of the  cur­
       rent  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-switch­
       ing.   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  appli­
       cation 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

       rupt 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  out­
       put  that screen has accumulated from the interrupted pro­
       gram to be flushed.  One disadvantage is that the  virtual
       terminal's  memory contains the non-flushed version of the
       output, which in rare cases can cause  minor  inaccuracies
       in  the  output.   For  example, if you switch screens and
       return, or update the screen with "C-a l"  you  would  see
       the  version  of  the output you would have gotten without
       "interrupt" being on.  Also, you might need  to  turn  off
       flow-control  (or  use auto-flow mode to turn it off auto­
       matically) 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 phys­
       ical  terminal when flow-control is enabled.  If this hap­
       pens, 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  dis­
       played  is  the actual command name of the program created
       in the window.  However, it is sometimes useful to distin­
       guish  various  programs of the same name or to change the
       name on-the-fly to reflect the current state of  the  win­
       dow.

       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.   Interac­
       tively,   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 cur­
       rent command running in the  window  to  the  end  of  the

       rent 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  por­
       tion  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 shellti­
       tle.  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  win­
       dow 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

       command, and revert to simply "root:" at its completion.

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

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

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

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

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

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

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


THE VIRTUAL TERMINAL

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

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

       When screen tries  to  figure  out  a  terminal  name  for

       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 sup­
       port 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 vir­
       tual 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 termi­
       nal 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 capa­
       bilities  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 term­
       cap.

       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 charac­
       ter  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 sequence the terminal uses to  enable  and  start  the
       graphics character set rather than SI.  `E0' is the corre­
       sponding 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'  ter­
       minfo capability.

       When  the  `po'  and  `pf' capabilities are present in the
       terminal's termcap entry, applications running in a screen
       window  can  send output to the printer port of the termi­
       nal.  This allows a user to have  an  application  in  one
       window sending output to a printer connected to the termi­
       nal, while all other windows are still active (the printer
       port  is enabled and disabled again for each chunk of out­
       put).  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 dis­
       play  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  imple­
       mented  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  pro­
       cesses.

       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


       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   interpreta­
                                  tion.

       ESC _                 (A)  Application   Program   Command
                                  (Hardstatus)

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

       ESC ] 83 ; cmd ^G     (A)  Execute  screen  command.  This
                                  only works if  multi-user  sup­
                                  port  is  compiled into screen.
                                  The pseudo-user  ":window:"  is
                                  used  to  check the access con­
                                  trol list. Use "addacl :window:
                                  -rwx  #?" to create a user with

                                  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  Cur­
                                  sor

                  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 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:  Itali­
                                  cized)

                  4               Underlined

                  5               Blinking

                  7               Negative Image

                  22         (A)  Normal Intensity

                  23         (A)  Standout Mode off (ANSI: Itali­
                                  cized 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


                  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


                  ?25        (V)  Visible Cursor

                  ?1000      (V)  VT200 mouse tracking

       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 spe­
                                  cial)

       ESC [ c                    Send    VT100    Identification
                                  String

       ESC [ x                    Send Terminal Parameter Report

       ESC [ > c                  Send   VT220  Secondary  Device
                                  Attributes String

       ESC [ 6 n                  Send Cursor Position Report


INPUT TRANSLATION

       In order to do a full VT100 emulation screen has to detect
       that a sequence of characters in the input stream was gen­
       erated by a keypress on the user's keyboard and insert the
       VT100  style  escape  sequence. Screen has a very flexible
       way of doing this by making it possible to  map  arbitrary
       commands  on  arbitrary sequences of characters. For stan­
       dard VT100 emulation the  command  will  always  insert  a
       string in the input buffer of the window (see also command
       stuff in the command table).  Because the sequences gener­
       ated by a keypress can change after a reattach from a dif­
       ferent terminal type, it is possible to bind  commands  to
       the termcap name of the keys.  Screen will insert the cor­
       rect 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)

                                         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[22~
       Function key 12       F2          stuff \033[23~
       Backspace             kb          stuff \010
       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)

                                         stuff \033On    (A)
       Keypad ,              f,          stuff ,
                                         stuff \033Ol    (A)
       Keypad enter          fe          stuff \015
                                         stuff \033OM    (A)


SPECIAL TERMINAL CAPABILITIES

       The  following  table  describes all terminal capabilities
       that are recognized by screen and are  not  in  the  term­
       cap(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 mar­
                    gins'). 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. Sun­
                    View(tm) example: '\E[8;%d;%dt'.

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

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

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

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

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

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

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

                    for more details.

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

       KJ   (str)   Set the kanji type  of  the  terminal.  Valid
                    strings are "jis", "euc" and "sjis".

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

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

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

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

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

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


CHARACTER TRANSLATION

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

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

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

       A  <charset-mapping> tells screen how to map characters in
       font <designator> ('B': Ascii, 'A': UK, 'K': german, etc.)
       to  strings.  Every  <mapping>  describes to what string a
       single character will be translated. A template  mechanism
       is  used, as most of the time the codes have a lot in com­
       mon (for example strings to switch  to  and  from  another
       charset).  Each  occurrence of '%' in <template> gets sub­
       stituted with the <template-arg> specified  together  with
       the  character.  If  your  strings are not similar at all,

       <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  corre­
       sponding  <designator>.  In this special case the template
       is assumed to be  just  '%'  because  the  charset  switch
       sequence  and the character mappings normally haven't much
       in common.

       This example shows one use of the extension:

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

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


ENVIRONMENT

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

       .../screen-3.?.??/etc/screenrc
       .../screen-3.?.??/etc/etcscreenrc Examples  in  the screen
                                         distribution package for
                                         private  and global ini­
                                         tialization files.
       $SYSSCREENRC
       /etc/screenrc                     screen    initialization
                                         commands
       $SCREENRC
       $HOME/.screenrc                   Read       in      after
                                         /etc/screenrc
       $SCREENDIR/S-<login>
       /local/screens/S-<login>          Socket       directories
                                         (default)
       /usr/tmp/screens/S-<login>        Alternate  socket direc­
                                         tories.
       <socket directory>/.termcap       Written by the "termcap"
                                         output function
       /usr/tmp/screens/screen-exchange  or
       /tmp/screen-exchange              screen     `interprocess
                                         communication buffer'
       hardcopy.[0-9]                    Screen images created by
                                         the hardcopy function
       screenlog.[0-9]                   Output log files created
                                         by the log function
       /usr/lib/terminfo/?/*             or
       /etc/termcap                      Terminal      capability
                                         databases
       /etc/utmp                         Login records
       $LOCKPRG                          Program   that  locks  a
                                         terminal.


SEE ALSO

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


AUTHORS

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


COPYLEFT

       Copyright (C) 1993-2001
            Juergen Weigert (jnweiger@immd4.informatik.uni-erlangen.de)
            Michael Schroeder (mlschroe@immd4.informatik.uni-erlangen.de)
       Copyright (C) 1987 Oliver Laumann
       This program is free software;  you  can  redistribute  it
       and/or modify it under the terms of the GNU General Public
       License as published  by  the  Free  Software  Foundation;
       either version 2, or (at your option) any later version.
       This  program  is  distributed in the hope that it will be
       useful, but WITHOUT ANY WARRANTY; without even the implied

       PURPOSE.  See the GNU  General  Public  License  for  more
       details.
       You  should have received a copy of the GNU General Public
       License along with this program (see the file COPYING); if
       not,  write to the Free Software Foundation, Inc., 59 Tem­
       ple Place - Suite 330, Boston, MA  02111-1307, USA


CONTRIBUTORS

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


VERSION

       This is version 3.9.9. Its roots are a merge of  a  custom
       version  2.3PR7  by Wayne Davison and several enhancements
       to Oliver Laumann's version 2.0. Note  that  all  versions
       numbered 2.x are copyright by Oliver Laumann.


AVAILABILITY

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


BUGS

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


       ·  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.  Spe­
          cial permission may also be required to write the  file
          "/etc/utmp".

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

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

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

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

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

       ·  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 man­
          ually.

       ·  A  weird imagination is most useful to gain full advan­
          tage of all the features.

       ·  Send bug-reports, fixes, enhancements, t-shirts, money,



Man(1) output converted with man2html