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man:start [2016-05-18 11:45]
87.152.18.246
man:start [2021-02-19 20:14] (current)
asciiphil old revision restored (2018-08-15 13:09)
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 ''screen -r //sessionowner//%%/[[%%//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 [[commands: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 "''[[commands:screen|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 "''[[commands:colon|C-a :]]''" command line) and then using it just like the "''[[commands:screen|C-a c]]''" command.  In addition, new windows can be created by running a command like:
 +
 +<code>
 +screen emacs prog.c
 +</code>
 +
 +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 "''[[commands:login|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:  "''[[commands:help|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 ====== ====== Command-Line Options ======
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 See [[Default Key Bindings]]. See [[Default Key Bindings]].
  
 +====== Customization ======
  
 +See [[Customization]].
  
 ====== The Message Line ====== ====== The Message Line ======
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 See [[Flow-Control]]. See [[Flow-Control]].
 +
 +====== Session Name (naming sessions) ======
 +
 +See [[:sessionnames]]
  
 ====== Titles (naming windows) ====== ====== Titles (naming windows) ======
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 See [[Character Translation]]. See [[Character Translation]].
  
 +====== 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 ======
  
 +| $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 [[commands:dumptermcap|termcap output function]] |
 +| /usr/tmp/screens/screen-exchange\\ /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/?/*\\ /etc/termcap                     | Terminal capability databases |
 +| /var/run/utmp                    | Login records |
 +| $LOCKPRG                         | Program that locks a terminal. |
  
 ====== See Also ====== ====== See Also ======
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   * Pablo Averbuj (pablo@averbuj.com).   * 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 ====== ====== Availability ======

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