X window system server for Mac OS

Xquartz [ options ]

The X window server for Mac OS provided by Apple. runs in parallel with Aqua in rootless mode. shares display with Mac OS. 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 Mac OS X handles the desktop background.


Customized using the defaults write org.macosforge.xquartz.X11 option

enable_fake_buttons -boolean true
Emulates a 3 button mouse using modifier keys. Default,
Command emulates button 2
Option button 3.
That is: clicking the first mouse button while holding down Command will act like clicking button 2. Holding down Option will simulate button 3.
fake_button2 modifiers
-fakemouse2 modifiers
Change the modifier keys used to emulate the second mouse button. Command is used to emulate the second button.
Any combination of names may be used: {l,r,}shift, {l,r,}option, {l,r,}control, {l,r,}command, fn
fake_button3 modifiers
-fakemouse3 modifiers
Change the modifier keys …
fullscreen_hotkeys -boolean true Enable OS hotkeys while in fullscreen
fullscreen_menu -boolean true Show the OS menu while in fullscreen
no_quit_alert -boolean true Disables the alert dialog displayed when attempting to quit
no_auth -boolean true Stops the X server requiring that clients authenticate themselves when connecting. See Xsecurity(7).
nolisten_tcp -boolean false tell the server to listen and accept TCP connections. Doing this without enabling xauth is a possible security concern. See Xsecurity(7).
enable_system_beep -boolean false Don't use the standard system beep effect for X11 alerts.
enable_key_equivalents -boolean false Disable menu keyboard equivalents while X11 windows are focused.
depth 12|24|-1
-depth 12|24|-1
color bit depth bits per pixel. -1 defaults to the depth of the main display.
sync_keymap -boolean true Keep the X11 keymap up to date with the OS system keymap.
option_sends_alt -boolean true Option key will send Alt_L and Alt_R instead of Mode_switch.
sync_pasteboard -boolean true Enable syncing between the OSX pasteboard and clipboard/primary selection buffers in X11. needs to be true for any of the other pasteboard sync options to have an effect.
sync_pasteboard_to_clipboard -boolean true Update the X11 CLIPBOARD when the OS NSPasteboard is updated.
sync_pasteboard_to_primary -boolean true Update the the X11 PRIMARY buffer when the OS NSPasteboard is updated.
sync_clipboard_to_pasteboard -boolean true Update the the OSX NSPasteboard when the X11 CLIPBOARD is updated. causes the clipboard synchronization to act as a clipboard manager in X11. This makes it impossible to use xclipboard, klipper, or any other such clipboard managers. To use any of these programs, disable .
sync_primary_on_select -boolean true defaults to false and is provided only "for experts." It updates the NSPasteboard whenever a new X11 selection is made (rather than requiring cmd-c to copy the selection to the NSPasteboard). Since the X11 protocol does not require applications to send notification when they change selection, this might not work in all cases (if you run into this problem, try selecting text in another application first, then selecting the text you want).
enable_test_extensions -boolean true defaults to false and is only accessible through the command line.
Enable to turn on the DEC-XTRAP, RECORD, and XTEST extensions in the server.
write __laucnd_id_prefix__.X11 scroll_in_device_direction -boolean true defaults to false.
ensure that X11 scroll events are always in the direction of the device. overrides the option in the Mouse/Trackpad section of System Preferences.


stores a server log at ~/Library/Logs/X11.org.macosforge.xquartz.log which is analogous to /var/log/Xorg.#.log on systems that use the XFree86 DDX such as Linux, BSD, and Solaris.

In addition using asl to the org.macosforge.xquartz facility. watch these logs using:

$ syslog -w -k Facility eq org.macosforge.xquartz
or include extra information such as the file, line, and function where the message originated:
$ syslog -w -F '$(Time) $(Sender) <$(Level)> $(File):$(Line) $(Function) :: $(Message)' -k Facility eq org.macosforge.xquartz
By default, sets an ASL mask which prevents logging messages below the ASL_LEVEL_WARNING level (meaning most logging is done to the file referenced above).
To force log messages to syslogd(8), adjust this mask using :
$ syslog -c X11.bin -d
The stdout and stderr messages by any process launched by XQuartz will be redirected to this syslog facility with a priority level of ASL_LEVEL_INFO and ASL_LEVEL_NOTICE .
In order to see these messages in syslog, adjust XQuartz's asl mask as above using -i or -n instead of -d.


X(7), Xserver(1), xdm(1), xinit(1), syslogd http://xquartz.macosforge.org


Apr 29 20:46:25 (org.macosforge.xquartz.(3 launchd check-in failed: No such process
Apr 29 20:46:25 (org.macosforge.xquartz.(4 Xquartz: Unable to locate waiting server: org.macosforge.xquartz.X11
Apr 29 20:46:25 (org.macosforge.xquartz.(5 Xquartz: Starting X server: /Applications/Utilities/XQuartz.app/Contents/MacOS/X11 --listenonly
Apr 29 20:46:25 (org.macosforge.xquartz.(3 Xquartz: start_x11_server: (ipc/mig) server died