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+@c This is part of the Emacs manual.
+@c Copyright (C) 2021--2022 Free Software Foundation, Inc.
+@c See file emacs.texi for copying conditions.
+@node Haiku
+@appendix Emacs and Haiku
+@cindex Haiku
+
+  Haiku is a Unix-like operating system that originated as a
+re-implementation of the operating system BeOS.
+
+  This section describes the peculiarities of using Emacs built with
+the Application Kit, the windowing system native to Haiku.  The
+oddities described here do not apply to using Emacs on Haiku built
+without windowing support, or built with X11.
+
+@menu
+* Haiku Basics::        Basic Emacs usage and installation under Haiku.
+* Haiku Fonts::         The various options for displaying fonts on Haiku.
+@end menu
+
+@node Haiku Basics
+@section Installation and usage peculiarities under Haiku
+@cindex haiku application
+@cindex haiku installation
+
+  Emacs installs two separate executables under Haiku; it is up to the
+user to decide which one suits him best: A regular executable, with
+the lowercase name @code{emacs}, and a binary containing
+Haiku-specific application metadata, with the name @code{Emacs}.
+
+@cindex launching Emacs from the tracker
+@cindex tty Emacs in haiku
+  If you are launching Emacs from the Tracker, or want to make the
+Tracker open files using Emacs, you should use the binary named
+@code{Emacs}; if you are going to use Emacs in the terminal, or wish
+to launch separate instances of Emacs, or do not care for the
+aforementioned system integration features, use the binary named
+@code{emacs} instead.
+
+@cindex modifier keys and system keymap (Haiku)
+@cindex haiku keymap
+  On Haiku, unusual modifier keys such as the Hyper key are
+unsupported.  By default, the super key corresponds with the option
+key defined by the operating system, the meta key with the command
+key, the control key with the system control key, and the shift key
+with the system shift key.  On a standard PC keyboard, Haiku should
+map these keys to positions familiar to those using a GNU system, but
+this may require some adjustment to your system's configuration to
+work.
+
+  It is impossible to type accented characters using the system super
+key map.
+
+  You can customize the correspondence between modifier keys known to
+the system, and those known to Emacs.  The variables that allow for
+that are described below.
+
+@cindex modifier key customization (Haiku)
+@table @code
+@vindex haiku-meta-keysym
+@item haiku-meta-keysym
+The system modifier key that will be treated as the Meta key by Emacs.
+It defaults to @code{command}.
+
+@vindex haiku-control-keysym
+@item haiku-control-keysym
+The system modifier key that will be treated as the Control key by
+Emacs.  It defaults to @code{control}.
+
+@vindex haiku-super-keysym
+@item haiku-super-keysym
+The system modifier key that will be treated as the Super key by
+Emacs.  It defaults to @code{option}.
+
+@vindex haiku-shift-keysym
+@item haiku-shift-keysym
+The system modifier key that will be treated as the Shift key by
+Emacs.  It defaults to @code{shift}.
+@end table
+
+The value of each variable can be one of the symbols @code{command},
+@code{control}, @code{option}, @code{shift}, or @code{nil}.
+@code{nil} or any other value will cause the default value to be used
+instead.
+
+@cindex tooltips (haiku)
+@cindex haiku tooltips
+  On Haiku, Emacs defaults to using the system tooltip mechanism.
+This usually leads to more responsive tooltips, but the tooltips will
+not be able to display text properties or faces.  If you need those
+features, customize the variable @code{use-system-tooltips} to the
+@code{nil} value, and Emacs will use its own implementation of
+tooltips.
+
+@cindex X resources on Haiku
+  Unlike the X window system, Haiku does not have a system-wide
+resource database.  Since many important options are specified via
+X resources (@pxref{X Resources}), an emulation is provided: upon
+startup, Emacs will load a file named @file{GNU Emacs} inside the user
+configuration directory (normally @file{/boot/home/config/settings}),
+which should be a flattened system message where keys and values are
+both strings, and correspond to attributes and their values
+respectively.
+
+You can create such a file with the @command{xmlbmessage} tool.
+
+@subsection What to do when Emacs crashes
+@cindex crashes, Haiku
+@cindex haiku debugger
+@vindex haiku-debug-on-fatal-error
+  If the variable @code{haiku-debug-on-fatal-error} is non-nil, Emacs
+will launch the system debugger when a fatal signal is received.  It
+defaults to @code{t}.  If GDB cannot be used on your system, please
+attach the report generated by the system debugger when reporting a
+bug.
+
+@node Haiku Fonts
+@section Font and font backend selection on Haiku
+@cindex font backend selection (Haiku)
+
+  Emacs, when built with Haiku windowing support, can be built with
+several different font backends.  You can specify font backends by
+specifying @kbd{-xrm Emacs.fontBackend:BACKEND} on the command line
+used to invoke Emacs, where @kbd{BACKEND} is one of the backends
+specified below, or on a per-frame basis by changing the
+@code{font-backend} frame parameter.
+
+  Two of these backends, @code{ftcr} and @code{ftcrhb} are identical
+to their counterparts on the X Window System.  There is also a
+Haiku-specific backend named @code{haiku}, that uses the App Server to
+draw fonts, but does not at present support display of color font and
+emoji.