====== screen's Appearance ======
===== Basics =====
The commands in this section include things that allow ''screen'' to
communicate information to the user (like the ''[[commands:info]]''
command) and things that change how ''screen'' looks (like the
''[[commands:caption]]'' command).
The information-providing commands are pretty simple:
''[[commands:info|C-a i]]'' gives some information about the current
window; ''[[commands:time|C-a t]]'' displays some information about the
system on which ''screen'' is running (including the current time);
''[[commands:lastmsg|C-a m]]'' redisplays the last message that ''screen''
displayed (in case you missed it); ''[[commands:version|C-a v]]'' displays
information about the version of ''screen'' that's running; and
''[[commands:license|C-a ,]]'' displays the license information screen
that is shown at ''screen'' startup by default.
===== Extras =====
==== Hardstatus Lines ====
Some terminals, mostly hardware serial terminals, have a separate area of
their display that is reserved as a status line. Many modern graphical
terminals use the titlebar of the window for such status information.
''screen'' calls this a
"hardstatus line". When ''screen'' starts, it checks to see if the
''hs'' termcap capability is set; if so, it assumes that there's a
hardstatus line present. If there's a hardstatus line and the
''[[commands:hardstatus]]'' option is set to "on" (which is the default
setting), ''screen'' will use the hardstatus line to display status
messages.
''screen'' also advertises the hardstatus capability to programs running
in its windows. When a program uses the hardstatus escape sequence
(''ESC_//string//ESC\'') or the ''xterm'' title escape sequence
(''ESC]0;//string//^G''), ''screen'' stores that //string// on a
per-window basis. The per-window hardstatus string can also be changed
with the ''[[commands:hstatus]]'' command (and the default hstatus for new
windows can be set with ''[[commands:defhstatus]]'').
The ''[[commands:hardstatus]]'' command can also be used to set a string
that will be displayed in the hardstatus line when ''screen'' isn't using
it to display messages. The string can contain any of ''screen'''s
[[man:string escapes]]. The default value is ''%h'', which just displays
the current window's hstatus string.
==== Status Bar ====
One of the most common things that ''screen'' users want to do is to have
some sort of status bar at the bottom (or top) of the display. ''screen''
provides several ways to do this.
If your terminal has a hardstatus line (as discussed above), you can use
the ''[[commands:hardstatus]]'' string as a status bar. If you don't have
a hardstatus line, you have two choices. The first is to use the command
''[[commands:hardstatus]] lastline'', which tells ''screen'' to reserve
the last line of the display for use as a hardstatus line. With a
''[[commands:hardstatus]] string //param//'' command, you will get a
status bar at the bottom of your display.
The second option is to use the ''[[commands:caption]]'' command. When
the display is split into multiple regions (see [[Region Management]] for
more details), ''screen'' puts a caption at the bottom of each region.
You can use the ''[[commands:caption]] always'' command to always display
the caption, even if the display is not split. Just as with
''[[commands:hardstatus]]'', there's a ''[[commands:caption]] string
//param//'' command that can be used to make a status bar. It uses all
the same [[man:string escapes]] that the ''[[commands:hardstatus]]''
command does.
There are tradeoffs for each of the two approaches. One big one is that
it's common to (ab)use the hardstatus capability to
[[faq#how_can_screen_use_xterm_s_title_bar|put things into ''xterm'''s
title bar]]. If you plan to do that, you'll need to use the caption for
your status bar. Another tradeoff is that you might want different
information available in the captions for split displays than in your main
status bar. In that case, you'd want to use the hardstatus line for the
status bar.
==== Bells ====
''screen'' can either use an audible bell or a visual bell, as controlled
by the ''[[commands:vbell]]'' command. If ''[[commands:vbell]]'' is off,
when ''screen'' receives an ASCII BEL character in the current window, it
sends a bell character (usually an ASCII BEL, but it depends on what the
terminal's termcap says) to the display (which will, presumably, beep).
If ''[[commands:vbell]]'' is on, when ''screen'' receives a BEL character,
it either triggers the display terminal's visual bell, if the terminal's
termcap has a ''vb'' capability, or it flashes the screen and displays the
''[[commands:vbell_msg]]''. ''[[commands:vbell|C-a C-g]]'' will toggle
''[[commands:vbell]]'' on and off.
If ''screen'' receives a bell in a window other than the current one, it
displays the ''[[commands:bell_msg]]'' onscreen.
==== Window Size ====
A ''screen'' window does not have to be the same size as the display
that's connected to it, although ''screen'' will resize windows to the
display when you switch to them. This only applies to the first display
showing the window; if another connected display, either from the ''-x''
[[man:Command-Line Options|command-line option]] or from a [[:multiuser]]
session, switches to an already-displayed window, the window keeps the
size set by the first display.
The ''[[commands:height]]'' command can change either the height or the
height and width of a window. (If you want to just change the width, use
the ''[[commands:width]]'' command, which is exactly like
''[[commands:height]]'' with the arguments reversed.) If the display's
termcap supports it, screen will change both the display terminal's and
the current window's dimensions. You can specify changing just the
display or just the window with the ''-d'' and ''-w'' options,
respectively.
If a window's dimensions have gotten out of sync with a display's, you can
use the ''[[commands:fit|C-a F]]'' command to resize the window to the
display.
===== Command Line =====
* ''-A'' - Disables one aspect of screen's default behavior: Normally, if the terminal can be resized, then screen will resize the terminal to fit the dimensions of the windows it's displaying. When ''-A'' is given, resizable terminals work just like nonresizable terminals--the windows are resized to fit the dimensions of the display. (See below for Windows PuTTY)
===== Keybindings =====
* ''C-a C'' - (''[[commands:clear]]'') Clears the current window.
* ''C-a F'' - (''[[commands:fit]]'') Fits the current window to the display's dimensions.
* ''C-a C-g'' - (''[[commands:vbell]]'') Toggles visual bell mode.
* ''C-a i'' - (''[[commands:info]]'') Displays information about the current window.
* ''C-a m'' - (''[[commands:lastmsg]]'') Redisplays the last message for this display.
* ''C-a t'' - (''[[commands:time]]'') Displays system information.
* ''C-a v'' - (''[[commands:version]]'') Displays screen's version information.
* ''C-a W'' - (''[[commands:width]]'') Toggles the display between 80 and 132 columns.
* ''C-a ,'' - (''[[commands:license]]'') Displays screen's license information.
===== Commands =====
* ''[[commands:attrcolor]]'' - Remaps the effect of text attributes.
* ''[[commands:autonuke]]'' - Determines whether a given window will attempt to display buffered text after a clear command is received.
* ''[[commands:bell_msg]]'' - Changes the message printed when a bell character is received in another window.
* ''[[commands:caption]]'' - Controls the display of the caption line at the bottom of screen windows.
* ''[[commands:clear]]'' - Clears the current window, but puts its text into the scrollback buffer.
* ''[[commands:defautonuke]]'' - Changes the default ''[[commands:autonuke]]'' setting for new windows.
* ''[[commands:defhstatus]]'' - Sets the default hardstatus line for new windows.
* ''[[commands:echo]]'' - Displays a message on the current display as if it were a screen message.
* ''[[commands:fit]]'' - Resizes the window to fit the current display region.
* ''[[commands:height]]'' - Changes the dimensions of the window or the display.
* ''[[commands:info]]'' - Display information about screen and the current window in the message area.
* ''[[commands:license]]'' - Displays screen's license, as happens when screen starts up.
* ''[[commands:nethack]]'' - Controls the use of nethack-themed messages from ''screen''.
* ''[[commands:hardstatus]]'' - Controls use of the terminal's hardstatus line (if any) for displaying screen messages.
* ''[[commands:hstatus]]'' - Synonym for ''[[commands:hardstatus]] string //status//''.
* ''[[commands:lastmsg]]'' - Redisplays the last message that screen showed on the current display.
* ''[[commands:msgminwait]]'' - Sets the minimum length of time that a screen message will be visible even if the user interacts with screen.
* ''[[commands:msgwait]]'' - Sets the length of time that a message will remain visible if the user does not interact with screen during the lifetime of the message.
* ''[[commands:sorendition]]'' - Defines the visual appearance of screen's messages.
* ''[[commands:startup_message]]'' - Enables or disables the display of screen's license information when screen starts up.
* ''[[commands:time]]'' - Displays (or controls the display of) system information.
* ''[[commands:vbell]]'' - Sets or toggles the visual bell.
* ''[[commands:vbell_msg]]'' - Sets or displays the message displayed for visual bells.
* ''[[commands:vbellwait]]'' - Defines a hysteresis for visual bells.
* ''[[commands:version]]'' - Uses the message area to display screen's version and compile date.
* ''[[commands:wall]]'' - Like ''[[commands:echo]]'', but sends the message to all displays, with the name of the current user prepended.
* ''[[commands:width]]'' - Like ''[[commands:height]]'', but with the order of arguments reversed.
===== Examples =====
==== Status Bar Examples ====
=== Simple window list ===
You can force the status line to always stay at the bottom of the screen
and set up a statusline string that displays the window information by
adding either of these to your .screenrc:
hardstatus alwayslastline "%w"
caption always "%w"
=== Highlighted current window ===
This puts the current window in bold and surrounded by brackets:
caption always "%{-b ..}%-w%{+b ..}[[%n%f*%t]]%{-}%+w"
=== Window list centered on current window ===
See the examples in [[truncation/padding escapes]], particularly the last
example.
=== Centered window list ===
This small snippet for your .screenrc uses both the caption and hardstatus
line to give a two-line statusbar at the bottom of the display. The upper
line (the caption line) consists of the number and name of all open
windows, black on white background, with the active window centered and
highlighted. The lower line (the hardstatus line) shows the window
number, window name and the window's hardstatus in white on black.
hardstatus alwayslastline "%= %3n %t%? [%h]%? %="
caption always "%= %-w%L>%{= BW}%n*%t%{-}%52<%+w %L="
=== Status bar and xterm title ===
In this section, we'll build up a configuration that uses the ''xterm''
title bar as a hardstatus line and displays a status bar at the bottom of
the screen.
To start with, we'll tell screen that ''xterm''s (and some other terminals
that use the same escape sequences) do have a hardstatus line, and we'll
use the escape sequences for setting the title bar as the hardstatus
escape sequences:
termcapinfo xterm*|Eterm|mlterm "hs:ts=\E]0;:fs=\007:ds=\E]0;screen\007"
Title bars aren't good places for actual status messages, so we'll tell
screen not to use the hardstatus line for status messages (they'll be
displayed at the bottom of the screen, just as if there was no hardstatus
line):
hardstatus off
We'll set the hardstatus string to show us the number and title of the
current window, as well as the window's hstatus string. Because of the
''%?'' escapes, the brackets are only shown if the window has an hstatus
string:
hardstatus string "screen %n (%t)%? [%h]%?"
Finally, we have the caption that makes for our status bar at the bottom
of the screen. It makes use of the ''%F'' escape to change the colors
depending on whether it's attached to the window with the focus. This
causes the currently-focused window to stand out.
If the caption is on a non-focused window, the entire bar is blue text on
a blue background (so it just looks blue), with the exception of the
window's information, which is blue on yellow. The focused (or only)
window's caption has a blue-on-cyan information section with the date and
computer name, followed by the window list in white on blue. The current
window is centered in the window list and is displayed in blue on yellow:
caption always "%?%F%{-b bc}%:%{-b bb}%?%C|%D|%M %d|%H%?%F%{+u wb}%? %L=%-Lw%45>%{+b by}%n%f*%t%{-}%+Lw%-0<"
===== Screen resizing despite -A when using PuTTY on Windows, iTerm2 on Mac OS X =====
With GNU ''screen'' 2009-05-15 ([[git://git.savannah.gnu.org/screen.git]] :: 9cdf8e20), the resize disable command line option ''-A'' does not work with PuTTY on Windows (0.60). One way to work around this is to disable the terminal feature for remote-controlled terminal resizing in PuTTY. This setting is found in "Terminal" > "Features" > "Disable remote-controlled terminal resizing". After this you do not need to specify ''-A'' since ''screen'' will now force a resizing.
The same problem occurs with iTerm 2 on Mac OS X, and the solution is approximately the same: in your profile, select the ''terminal'' tab, then mark the checkbox ''Disable session-initiated window resizing''.