                       XFree86® on Darwin and Mac OS X

                               Torrey T. Lyons

                              15 December 2003

1.  Introduction

XFree86, a freely redistributable open-source implementation of the X Window
System, has been ported to Darwin and Mac OS X. This document is a collection
of information for anyone running XFree86 on Apple's next generation operat-
ing system.

Most of the current work on XFree86 for Darwin and Mac OS X is centered
around the XonX project at SourceForge. If you are interested in up-to-date
status, want to report a bug, or are interested in working on XFree86 for
Darwin, stop by the XonX project.

2.  Hardware Support and Configuration

The X window server for Darwin and Mac OS X provided by the XFree86 Project,
Inc. is called XDarwin. XDarwin can run in three different modes. On Mac
OS X, XDarwin runs in parallel with Aqua in full screen or rootless modes.
These modes are called Quartz modes, named after the Quartz 2D compositing
engine used by Aqua. XDarwin can also be run from the Darwin console in IOKit
mode.

In full screen Quartz mode, when the X Window System is active, it takes over
the entire screen. You can switch back to the Mac OS X desktop by holding
down Command-Option-A. This key combination can be changed in the user pref-
erences. From the Mac OS X desktop, click on the XDarwin icon in the Dock to
switch back to the X window system. (You can change this behavior in the user
preferences so that you must click the XDarwin icon in the floating switch
window instead.)

In rootless mode, the X window system and Aqua share your display.  The root
window of the X11 display is the size of the screen and contains all the
other windows. The X11 root window is not displayed in rootless mode as Aqua
handles the desktop background.

From the console, the Darwin port of XFree86 uses the IOKit for device driver
loading and discovery, rather than the XFree86 module loader.  Because of
this, the XFree86 configuration file is not used on Darwin or Mac OS X sys-
tems. The descriptions found elsewhere of devices supported by XFree86 for
other operating systems also do not apply.

XFree86 for Darwin or Mac OS X will work with any video card that you have an
IOKit driver for. If you are running Mac OS X, this typically means any card
that has been shipped by Apple. If a card works for you with the Mac OS X
GUI, it will work on the same machine with XFree86. If you have a pure Darwin
installation, you may need to download additional third-party drivers from
Apple's Darwin site. IOKit drivers are typically installed in /Sys-
tem/Library/Extensions/ or /Library/Extensions/.

Multi-button and scroll wheel mouse support works well with all USB mice that
I have tested. I have done no testing with ADB mice, but without a special
driver, only a single mouse button will work on an ADB mouse.

3.  Getting Started

Following are instructions for building and running your own copy of XFree86.
The procedure for getting your X server up and running on Darwin and Mac OS X
are very similar. Where there are differences I have noted them below. Note
that to build XFree86 for yourself on Mac OS X, you need to install the
Developers' Tools.

If you don't feel the need to live on the cutting edge, you can save some
time and effort by using the precompiled binaries available on the XFree86
FTP server at <URL:ftp://ftp.xfree86.org/pub/XFree86/4.5.0/binaries/>.  Fol-
low the instructions in the Install document to install it. This will create
three new directory trees, /usr/X11R6, /etc/X11 and /etc/fonts. On Mac OS X
the Xquartz.tgz tarball is required in addition to the other tarballs
required on other platforms. With Mac OS X Quartz support, the XDarwin appli-
cation will be installed in /Applications.

If you get the precompiled binaries you can skip ahead to the section on run-
ning the X Window System (section 4., page 1) On the other hand, if you want
to build things yourself from scratch, follow the directions below.

3.1  Get the Code

The first thing you need to do is to get the source code from the XFree86
project.

   o  Setup CVS: Both Darwin and Mac OS X include CVS (Concurrent Versions
     System), which is an easy way to download and keep up to date with open
     source code released by XFree86 and others. You do have to setup CVS
     properly, however, to tell it where to look. Follow the XFree86 instruc-
     tions on how to do this either via ssh or via the cvs pserver.

   o  Now make a directory in some convenient place which will serve as your
     top level directory for you open source development efforts. I am going
     to call this directory sandbox/ in the following discussions and you
     could put this directory, for example, in ~/sandbox/.

   o From the command line type:

          cd sandbox
          cvs checkout xc

     Wait for all the files to complete downloading.

3.2  Build XFree86

Once you have everything ready it is easy to build and install XFree86. From
the command line:

     cd sandbox/xc
     make World >& world.log

     (wait for several hours)

     sudo make install >& install.log
     sudo make install.man >& man.log

4.  Run the X Window System

4.1  Setting Your Path

You need to add the X Window System executables to your path. Your path is
the list of directories to be searched for executable commands.  The X11 com-
mands are located in /usr/X11R6/bin, which needs to be added to your path. In
Quartz mode, the XDarwin application does this for you automatically. It can
also be configured to add additional directories where you have installed
command line applications. When running from the Darwin console, you will
need to set the path correctly for your shell as XDarwin will not do this for
you.

More experienced users will have already set their path correctly using the
initialization files for their shell. In this case, you can inform XDarwin
not to modify your path in the preferences. XDarwin launches the initial X11
clients in the user's default login shell. (An alternate shell can also be
specified in the preferences.) The way to set the path depends on the shell
you are using. This is described in the man page documentation for the shell.

In addition you may also want to add the man pages from XFree86 to the list
of pages to be searched when you are looking for documentation. The X11 man
pages are located in /usr/X11R6/man and the MANPATH environment variable con-
tains the list of directories to search.

4.2  Starting the X Server

On Mac OS X, you can run XFree86 from the Darwin text console or in parallel
with Aqua. To get to the text console in Mac OS X you need to logout and type
``>console'' as the user name. This will shutdown Core Graphics and bring up
the console login prompt. Login again as your user.  From the text console
you can start the X Window System by typing ``exec startx''.

When you are ready to quit XFree86 type ``exit'' in the main terminal window
or quit with the window manager if you have one running. Unfortunately in
IOKit mode, the X server does not shutdown correctly and if you did not start
with ``exec startx'', you will get an apparently frozen screen with only a
spinning beachball cursor on it. Nothing you type shows up on the screen, but
in fact your keystrokes are being received by the console. Type ``logout'' to
return to normalcy after a brief delay. With Darwin, this should put you back
at the text console login prompt. With Mac OS X, Core Graphics will restart
and you should be given a login window.

To start XFree86 in Quartz mode you can launch the XDarwin application in the
/Applications folder, or from the command line type ``startx -- -quartz''. By
default this will give you a mode picker to choose between full screen or
rootless mode. You can change the default to always use a particular mode in
the preferences, or you can specify the ``-fullscreen'' or ``-rootless''
options on the command line instead of ``-quartz''.

4.3  Double-clickable X11 Executables

Mac OS X 10.3 can be configured to automatically launch XDarwin when you dou-
ble-click an X11 executable in the Finder. When an executable file is double-
clicked Launch Services checks to see if it is linked against the X11
libraries. If it is, Launch Services opens the default X server.  To set the
default X server, do the following:

   o Create a simple file which ends in ''.x11app''.

   o Open the file with Get Info in the Finder.

   o Under ''Open with:'' select the XDarwin application.

   o Select ''Change All...'' to set XDarwin as the default.

On Mac OS X 10.3 the default X server is started when an X11 executable is
double-clicked, whether or not its extension is ''.x11app''. On previous ver-
sions of Mac OS X, an X11 executable must have a ''.x11app'' extension for
this to work.

4.4  Customize the X Window System

The X Window System is very customizable and you will certainly want to
change some things. There is a lot you can do to control how your windows
look, how the windows are moved, resized, etc. You will likely want to get a
fancier window manager than twm, which is included with XFree86. The .xinitrc
file in your home directory controls what programs are run when you start the
X Window System. You can find a sample .xinitrc file in /etc/X11/xinit/xini-
trc.

There are many window managers that have been ported to Darwin. The following
pages contain collections of window managers and other X window system
clients:

   o  DarwinPorts: An easy way to install various open-source software prod-
     ucts on Darwin and Mac OS X.

   o  Fink: A package manager that will easily download, compile, and install
     lots of open source software from the Internet.

   o  GNU-Darwin: A source for tons of software ported to Darwin.

Good luck!

     Generated from XFree86: xc/programs/Xserver/hw/xfree86/doc/sgml/Darwin.sgml,v 1.11 dawes Exp $

