Provided by: screen_4.0.3-13ubuntu4_i386 bug

NAME

       screen - screen manager with VT100/ANSI terminal emulation

SYNOPSIS

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

DESCRIPTION

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

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

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

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

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

              screen emacs prog.c

       from  a shell prompt within a previously created window.  This will not
       run another copy of screen, but will instead supply  the  command  name
       and  its  arguments  to  the  window  manager  (specified  in  the $STY
       environment variable) who will use it to create the  new  window.   The
       above  example would start the emacs editor (editing prog.c) and switch
       to its window. - Note that you cannot transport  environment  variables
       from  the  invoking  shell  to  the  application  (emacs in this case),
       because it is forked from the  parent  screen  process,  not  from  the
       invoking shell.

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

GETTING STARTED

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

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

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

COMMAND-LINE OPTIONS

       Screen has the following command-line options:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

       -v   Print version number.

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

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

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

DEFAULT KEY BINDINGS

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

       The following table shows the default key bindings:

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

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

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

       C-a tab     (focus)       Switch the input focus to  the  next  region.
                                 See also split, remove, only.

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

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

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

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

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

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

       C-a C       (clear)       Clear the screen.

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

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

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

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

       C-a C-g     (vbell)       Toggles screens visual bell mode.

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

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

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

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

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

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

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

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

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

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

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

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

       C-a Q       (only)        Delete all regions but the current one.   See
                                 also split, remove, focus.

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

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

       C-a S       (split)       Split  the  current region into two new ones.
                                 See also only, remove, focus.

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

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

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

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

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

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

       C-a X       (remove)      Kill the current  region.   See  also  split,
                                 only, focus.

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

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

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

       C-a ?       (help)        Show key bindings.

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

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

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

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

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

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

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

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

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

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

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

CUSTOMIZATION

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

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

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

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

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

       The following commands are available:

       acladd usernames [crypted-pw]
       addacl usernames

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

       aclchg usernames permbits list
       chacl usernames permbits list

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

       acldel username

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

       aclgrp username [groupname]

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

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

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

       activity message

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

                   ’Activity in window %n’

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

       allpartial on|off

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

       altscreen on|off

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

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

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

       attrcolor attrib [attribute/color-modifier]

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

       Examples:

              attrcolor b "R"

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

              attrcolor u "-u b"

       Use blue text instead of underline.

              attrcolor b ".I"

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

              attrcolor i "+b"

       Make bright colored text also bold.

       autodetach on|off

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

       autonuke on|off

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

       backtick id lifespan autorefresh cmd args...
       backtick id

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

       bce [on|off]

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

       bell_msg [message]

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

                   ’Bell in window %n’

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

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

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

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

       Some examples:

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

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

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

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

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

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

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

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

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

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

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

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

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

       break [duration]

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

       blanker

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

       blankerprg [program args]

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

       breaktype [tcsendbreak|TIOCSBRK |TCSBRK]

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

       bufferfile [exchange-file]

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

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

       c1 [on|off]

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

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

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

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

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

       charset set

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

       chdir [directory]

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

       clear

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

       colon [prefix]

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

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

       command [-c class]

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

       compacthist [on|off]

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

       console [on|off]

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

       copy

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

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

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

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

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

       copy_reg [key]

       No longer exists, use "readreg" instead.

       crlf [on|off]

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

       debug on|off

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

       defc1 on|off

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

       defautonuke on|off

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

       defbce on|off

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

       defbreaktype [tcsendbreak|TIOCSBRK |TCSBRK]

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

       defcharset [set]

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

       defescape xy

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

       defflow on|off|auto [interrupt]

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

       defgr on|off

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

       defhstatus [status]

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

       defencoding enc

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

       deflog on|off

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

       deflogin on|off

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

       defmode mode

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

       defmonitor on|off

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

       defnonblock on|off|numsecs

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

       defobuflimit limit

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

       defscrollback num

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

       defshell command

       Synonym to the shell command. See there.

       defsilence on|off

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

       defslowpaste msec"

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

       defutf8 on|off

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

       defwrap on|off

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

       defwritelock on|off|auto

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

       defzombie [keys]

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

       detach [-h]

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

       dinfo

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

       displays

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

       digraph [preset]

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

       dumptermcap

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

       echo [-n] message

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

       encoding enc [enc]

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

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

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

       escape xy

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

       eval command1 [command2 ...]

       Parses and executes each argument as separate command.

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

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

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

       Examples:

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

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

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

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

              exec !..| less
              |less

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

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

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

       fit

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

       flow [on|off|auto]

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

       focus [up|down|top|bottom]

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

       gr [on|off]

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

       hardcopy [-h] [file]

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

       hardcopy_append on|off

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

       hardcopydir directory

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

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

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

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

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

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

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

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

       help [-c class]

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

       history

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

       hstatus status

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

       idle [timeout [cmd args]]

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

       ignorecase [on|off]

       Tell  screen  to  ignore the case of characters in searches. Default is
       ‘off’.

       info

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

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

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

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

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

       ins_reg [key]

       No longer exists, use "paste" instead.

       kill

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

       lastmsg

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

       license

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

       lockscreen

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

       log [on|off]

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

       logfile filename
       logfile flush secs

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

       login [on|off]

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

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

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

       mapdefault

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

       mapnotnext

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

       maptimeout [timo]

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

       markkeys string

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

       maxwin num

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

       meta

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

       monitor [on|off]

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

       msgminwait sec

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

       msgwait sec

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

       multiuser on|off

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

       nethack on|off

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

       next

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

       nonblock [on|off|numsecs]

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

       number [n]

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

       obuflimit [limit]

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

       only

       Kill all regions but the current one.

       other

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

       partial on|off

       Defines whether the display should be  refreshed  (as  with  redisplay)
       after  switching  to  the current window. This command only affects the
       current window.  To immediately affect all windows use  the  allpartial
       command.  Default is ‘off’, of course.  This default is fixed, as there
       is currently no defpartial command.

       password [crypted_pw]

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

       paste [registers [dest_reg]]

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

       pastefont [on|off]

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

       pow_break

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

       pow_detach

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

       pow_detach_msg [message]

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

       prev

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

       printcmd [cmd]

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

       process [key]

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

       quit

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

       readbuf [-e encoding] [filename]

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

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

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

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

       redisplay

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

       register [-e encoding] key string

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

       remove

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

       removebuf

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

       reset

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

       resize

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

              resize +N   increase current region height by N

              resize -N   decrease current region height by N

              resize  N   set current region height to N

              resize  =   make all windows equally high

              resize  max maximize current region height

              resize  min minimize current region height

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

       Establish a new window.  The flow-control options (-f,  -fn  and  -fa),
       title  (a.k.a.) option (-t), login options (-l and -ln) , terminal type
       option (-T <term>), the all-capability-flag (-a) and scrollback  option
       (-h  <num>)  may be specified with each command.  The option (-M) turns
       monitoring on for this window.  The option (-L) turns output logging on
       for  this  window.  If an optional number n in the range 0..MAXWIN-1 is
       given, the window number n is assigned to the newly created window (or,
       if  this  number  is  already in-use, the next available number).  If a
       command is specified after  "screen",  this  command  (with  the  given
       arguments)  is  started  in  the window; otherwise, a shell is created.
       Thus, if your ".screenrc" contains the lines

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

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

       scrollback num

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

       select [WindowID]

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

       sessionname [name]

       Rename  the  current  session.  Note,  that for "screen -list" the name
       shows up with the process-id  prepended.  If  the  argument  "name"  is
       omitted,  the  name  of this session is displayed. Caution: Among other
       problems, the $STY environment variable still reflects  the  old  name.
       Use  of  this command is strongly discouraged. Use the "-S" commandline
       option if you need this feature.  The default is constructed  from  the
       tty and host names.

       setenv [var [string]]

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

       setsid [on|off]

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

       shell command

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

       shelltitle title

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

       silence [on|off|sec]

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

       silencewait sec

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

       sleep num

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

       slowpaste msec

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

       source file

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

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

       sorendition [attr [color]]

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

       split

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

       startup_message on|off

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

       stuff string

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

       su [username [password [password2]]

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

       suspend

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

       term term

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

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

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

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

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

       Some examples:

              termcap xterm*  LP:hs@

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

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

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

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

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

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

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

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

       time [string]

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

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

       title [windowtitle]

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

       unsetenv var

       Unset an environment variable.

       utf8 [on|off [on|off]]

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

       vbell [on|off]

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

       vbell_msg [message]

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

       vbellwait sec

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

       verbose [on|off]

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

       version

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

       wall message

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

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

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

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

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

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

       windows

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

       wrap [on|off]

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

       writebuf [-e encoding] [filename]

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

       writelock [on|off|auto]

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

       xoff
       xon

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

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

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

       zombie [keys[onerror]]
       defzombie [keys]

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

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

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

THE MESSAGE LINE

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

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

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

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

WINDOW TYPES

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

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

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

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

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

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

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

          b      BINARY. The connection is in binary mode.

          e      ECHO. Local echo is disabled.

          c      SGA. The connection is in ‘character  mode’  (default:  ‘line
                 mode’).

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

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

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

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

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

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

STRING ESCAPES

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

       Here is the full list of supported escapes:

       %      the escape character itself

       a      either ’am’ or ’pm’

       A      either ’AM’ or ’PM’

       c      current time HH:MM in 24h format

       C      current time HH:MM in 12h format

       d      day number

       D      weekday name

       f      flags of the window

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

       h      hardstatus of the window

       H      hostname of the system

       l      current load of the system

       m      month number

       M      month name

       n      window number

       s      seconds

       t      window title

       u      all other users on this window

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

       W      all window numbers and names except the current one

       y      last two digits of the year number

       Y      full year number

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

       :      else part of ’%?’

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

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

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

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

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

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

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

       +      add the specified set to the current attributes

       -      remove the set from the current attributes

       !      invert the set in the current attributes

       =      change the current attributes to the specified set

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

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

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

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

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

       Examples:

       "G"    set color to bright green

       "+b r" use bold red

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

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

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

FLOW-CONTROL

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

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

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

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

TITLES (naming windows)

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

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

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

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

       Here’s some .screenrc examples:

              screen -t top 2 nice top

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

                   shelltitle ’> |csh’
                   screen 1

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

              /usr/joe/src/dir> trn

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

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

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

                   % !em
                   emacs file.c

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

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

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

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

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

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

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

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

THE VIRTUAL TERMINAL

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

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

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

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

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

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

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

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

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

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

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

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

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

       ESC E                      Next Line

       ESC D                      Index

       ESC M                      Reverse Index

       ESC H                      Horizontal Tab Set

       ESC Z                      Send VT100 Identification String

       ESC 7                 (V)  Save Cursor and Attributes

       ESC 8                 (V)  Restore Cursor and Attributes

       ESC [s                (A)  Save Cursor and Attributes

       ESC [u                (A)  Restore Cursor and Attributes

       ESC c                      Reset to Initial State

       ESC g                      Visual Bell

       ESC Pn p                   Cursor Visibility (97801)

           Pn = 6                 Invisible

                7                 Visible

       ESC =                 (V)  Application Keypad Mode

       ESC >                 (V)  Numeric Keypad Mode

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

       ESC \                 (A)  String Terminator

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

       ESC !                      Global Message String (Message Line)

       ESC k                      A.k.a. Definition String

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

       ESC _                 (A)  Application Program Command (Hardstatus)

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

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

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

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

       ESC n                 (A)  Lock Shift G2

       ESC o                 (A)  Lock Shift G3

       ESC N                 (A)  Single Shift G2

       ESC O                 (A)  Single Shift G3

       ESC ( Pcs             (A)  Designate character set as G0

       ESC ) Pcs             (A)  Designate character set as G1

       ESC * Pcs             (A)  Designate character set as G2

       ESC + Pcs             (A)  Designate character set as G3

       ESC [ Pn ; Pn H            Direct Cursor Addressing

       ESC [ Pn ; Pn f            same as above

       ESC [ Pn J                 Erase in Display

             Pn = None or 0       From Cursor to End of Screen

                  1               From Beginning of Screen to Cursor

                  2               Entire Screen

       ESC [ Pn K                 Erase in Line

             Pn = None or 0       From Cursor to End of Line

                  1               From Beginning of Line to Cursor

                  2               Entire Line

       ESC [ Pn X                 Erase character

       ESC [ Pn A                 Cursor Up

       ESC [ Pn B                 Cursor Down

       ESC [ Pn C                 Cursor Right

       ESC [ Pn D                 Cursor Left

       ESC [ Pn E                 Cursor next line

       ESC [ Pn F                 Cursor previous line

       ESC [ Pn G                 Cursor horizontal position

       ESC [ Pn ‘                 same as above

       ESC [ Pn d                 Cursor vertical position

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

             Ps = None or 0       Default Rendition

                  1               Bold

                  2          (A)  Faint

                  3          (A)  Standout Mode (ANSI: Italicized)

                  4               Underlined

                  5               Blinking

                  7               Negative Image

                  22         (A)  Normal Intensity

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

                  24         (A)  Not Underlined

                  25         (A)  Not Blinking

                  27         (A)  Positive Image

                  30         (A)  Foreground Black

                  31         (A)  Foreground Red

                  32         (A)  Foreground Green

                  33         (A)  Foreground Yellow

                  34         (A)  Foreground Blue

                  35         (A)  Foreground Magenta

                  36         (A)  Foreground Cyan

                  37         (A)  Foreground White

                  39         (A)  Foreground Default

                  40         (A)  Background Black

                  ...             ...

                  49         (A)  Background Default

       ESC [ Pn g                 Tab Clear

             Pn = None or 0       Clear Tab at Current Position

                  3               Clear All Tabs

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

       ESC [ Pn I            (A)  Horizontal Tab

       ESC [ Pn Z            (A)  Backward Tab

       ESC [ Pn L            (A)  Insert Line

       ESC [ Pn M            (A)  Delete Line

       ESC [ Pn @            (A)  Insert Character

       ESC [ Pn P            (A)  Delete Character

       ESC [ Pn S                 Scroll Scrolling Region Up

       ESC [ Pn T                 Scroll Scrolling Region Down

       ESC [ Pn ^                 same as above

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

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

             Ps = 4          (A)  Insert Mode

                  20         (A)  Automatic Linefeed Mode

                  34              Normal Cursor Visibility

                  ?1         (V)  Application Cursor Keys

                  ?3         (V)  Change Terminal Width to 132 columns

                  ?5         (V)  Reverse Video

                  ?6         (V)  Origin Mode

                  ?7         (V)  Wrap Mode

                  ?9              X10 mouse tracking

                  ?25        (V)  Visible Cursor

                  ?47             Alternate Screen (old xterm code)

                  ?1000      (V)  VT200 mouse tracking

                  ?1047           Alternate Screen (new xterm code)

                  ?1049           Alternate Screen (new xterm code)

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

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

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

       ESC [ c                    Send VT100 Identification String

       ESC [ x                    Send Terminal Parameter Report

       ESC [ > c                  Send   VT220   Secondary  Device  Attributes
                                  String

       ESC [ 6 n                  Send Cursor Position Report

INPUT TRANSLATION

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

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

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

SPECIAL TERMINAL CAPABILITIES

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

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

       Z0   (str)   Change width to 132 columns.

       Z1   (str)   Change width to 80 columns.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

CHARACTER TRANSLATION

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

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

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

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

       Here is an example:

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

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

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

       This example shows one use of the extension:

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

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

ENVIRONMENT

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

FILES

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

SEE ALSO

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

AUTHORS

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

COPYLEFT

       Copyright (C) 1993-2003
            Juergen Weigert (jnweiger@immd4.informatik.uni-erlangen.de)
            Michael Schroeder (mlschroe@immd4.informatik.uni-erlangen.de)
       Copyright (C) 1987 Oliver Laumann
       This program is free software; you can redistribute it and/or modify it
       under the terms of the GNU General Public License as published  by  the
       Free  Software  Foundation;  either  version 2, or (at your option) any
       later version.
       This program is distributed in the hope that it  will  be  useful,  but
       WITHOUT   ANY   WARRANTY;   without   even   the  implied  warranty  of
       MERCHANTABILITY or FITNESS FOR  A  PARTICULAR  PURPOSE.   See  the  GNU
       General Public License for more details.
       You should have received a copy of the GNU General Public License along
       with this program (see the file COPYING); if not,  write  to  the  Free
       Software  Foundation,  Inc.,  59  Temple  Place - Suite 330, Boston, MA
       02111-1307, USA

CONTRIBUTORS

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

VERSION

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

AVAILABILITY

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

BUGS

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

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

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

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

       ·  Screen does not make use of hardware tabs.

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

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

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

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

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

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

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

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

       ·  Send bug-reports, fixes, enhancements, t-shirts, money, beer & pizza
          to screen@uni-erlangen.de.