+![Yo Dawg...](/screenshots/yodawg.png?raw=true "Yo Dawg, I heard you like text windowing systems, so I ran a text windowing system inside your text windowing system so you can have a terminal in your terminal.")
+
+![Sixel Pictures Of Cliffs Of Moher And Buoy](/screenshots/sixel_images.png?raw=true "Sixel Pictures Of Cliffs Of Moher And Buoy")
+
+![Sixel Color Wheel](/screenshots/sixel_color_wheel.png?raw=true "Sixel Color Wheel")
+
+
+
+System Properties
+-----------------
+
+The following properties control features of Jexer:
+
+ jexer.Swing
+ -----------
+
+ Used only by jexer.demos.Demo1 and jexer.demos.Demo4. If true, use
+ the Swing interface for the demo application. Default: true on
+ Windows (os.name starts with "Windows") and Mac (os.name starts with
+ "Mac"), false on non-Windows and non-Mac platforms.
+
+ jexer.Swing.cursorStyle
+ -----------------------
+
+ Used by jexer.backend.SwingTerminal. Selects the cursor style to
+ draw. Valid values are: underline, block, outline. Default:
+ underline.
+
+ jexer.Swing.tripleBuffer
+ ------------------------
+
+ Used by jexer.backend.SwingTerminal. If true, use triple-buffering
+ which reduces screen tearing but may also be slower to draw on
+ slower systems. If false, use naive Swing thread drawing, which may
+ be faster on slower systems but also more likely to have screen
+ tearing. Default: true.
+
+ jexer.TTerminal.ptypipe
+ -----------------------
+
+ Used by jexer.TTerminalWindow. If true, spawn shell using the
+ 'ptypipe' utility rather than 'script'. This permits terminals to
+ resize with the window. ptypipe is a separate C language utility,
+ available at https://gitlab.com/klamonte/ptypipe. Default: false.
+
+ jexer.TTerminal.closeOnExit
+ ---------------------------
+
+ Used by jexer.TTerminalWindow. If true, close the window when the
+ spawned shell exits. Default: false.
+
+ jexer.ECMA48.rgbColor
+ ---------------------
+
+ Used by jexer.backend.ECMA48Terminal. If true, emit T.416-style RGB
+ colors for normal system colors. This is expensive in bandwidth,
+ and potentially terrible looking for non-xterms. Default: false.
+
+ jexer.ECMA48.sixel
+ ------------------
+
+ Used by jexer.backend.ECMA48Terminal. If true, emit image data
+ using sixel, otherwise show blank cells where images could be. This
+ is expensive in bandwidth, very expensive in CPU (especially for
+ large images), and will leave artifacts on the screen if the
+ terminal does not support sixel. Default: true.
+
+
+
+Known Issues / Arbitrary Decisions
+----------------------------------
+
+Some arbitrary design decisions had to be made when either the
+obviously expected behavior did not happen or when a specification was
+ambiguous. This section describes such issues.
+
+ - See jexer.tterminal.ECMA48 for more specifics of terminal
+ emulation limitations.
+
+ - TTerminalWindow uses cmd.exe on Windows. Output will not be seen
+ until enter is pressed, due to cmd.exe's use of line-oriented
+ input (see the ENABLE_LINE_INPUT flag for GetConsoleMode() and
+ SetConsoleMode()).
+
+ - TTerminalWindow by default launches 'script -fqe /dev/null' or
+ 'script -q -F /dev/null' on non-Windows platforms. This is a
+ workaround for the C library behavior of checking for a tty:
+ script launches $SHELL in a pseudo-tty. This works on Linux and
+ Mac but might not on other Posix-y platforms.
+
+ - Closing a TTerminalWindow without exiting the process inside it
+ may result in a zombie 'script' process.
+
+ - When using the Swing backend, and not using 'ptypipe', closing a
+ TTerminalWindow without exiting the process inside it may result
+ in a SIGTERM to the JVM causing it to crash. The root cause is
+ currently unknown, but is potentially a bug in more recent
+ releases of the 'script' utility from the util-linux package.
+
+ - TTerminalWindow can only notify the child process of changes in
+ window size if using the 'ptypipe' utility, due to Java's lack of
+ support for forkpty() and similar. ptypipe is available at
+ https://gitlab.com/klamonte/ptypipe.
+
+ - Java's InputStreamReader as used by the ECMA48 backend requires a
+ valid UTF-8 stream. The default X10 encoding for mouse
+ coordinates outside (160,94) can corrupt that stream, at best
+ putting garbage keyboard events in the input queue but at worst
+ causing the backend reader thread to throw an Exception and exit
+ and make the entire UI unusable. Mouse support therefore requires
+ a terminal that can deliver either UTF-8 coordinates (1005 mode)
+ or SGR coordinates (1006 mode). Most modern terminals can do
+ this.
+
+ - jexer.session.TTYSession calls 'stty size' once every second to
+ check the current window size, performing the same function as
+ ioctl(TIOCGWINSZ) but without requiring a native library.
+
+ - jexer.backend.ECMA48Terminal calls 'stty' to perform the
+ equivalent of cfmakeraw() when using System.in/out. System.out is
+ also (blindly!) put in 'stty sane cooked' mode when exiting.
+
+ - jexer.backend.ECMA48Terminal uses a single palette containing
+ MAX_COLOR_REGISTERS colors for all sixel images. These colors are
+ generated in the SixelPalette.makePalette() method with bits for
+ hue, saturation, and luminance, and the two extremes set to pure
+ black and pure white. This provides a reasonable general-purpose
+ palette light on CPU, but at a cost that individual images do not
+ look as good as the terminal is actually capable of.
+
+
+
+See Also
+--------
+
+[Tranquil Java IDE](https://tjide.sourceforge.io) is a TUI-based
+integrated development environment for the Java language that was
+built using a very lightly modified GPL version of Jexer. TJ provided
+a real-world use case to shake out numerous bugs and limitations of
+Jexer.