Some good changes.. others are irritating if you’re a “power user”.

One of the nice changes is that you don’t have to run X11 if you have an X-Windows-based program. In fact it’s how a bad idea to do so is it leaves extra xterm processes running even when you quit.

One of the XDarwin maintainers ran over some of the changes and features on the Apple X11 Users Mailing list:

I’ve been meaning to get some real release notes out there, but instead, let’s have some casual, off the cuff ones!

Biggest architectural change in Leopard for X11: Switched from XFree86 codebase (based on, IIRC, X11R6.8) to codebase (X11R7.2)

Biggest user-visible change: launchd support for X11. The only situation where you should need to manually start is if you are only running remote X11 applications.

The way that this is accomplished is by some slight-of-hand with the $DISPLAY variable — if you look, it should be something like “/tmp/ launch-vbXRyu/:0”. If an X client connects to this, it will actually connect to launchd, which will start Xquartz if needed and pass the client’s socket to the server.

All of that should be invisible to you; the X client library (libX11.dylib) was modified to support this, and all X11 applications link against this library. “DISPLAY=:0” would still work if is already running, but it will not trigger X11 to launch.

Two biggest bugs:
Fullscreen support is broken. I know many of you will hate me for this — it stopped working when we switched codebases, and I was unable to get it working again. I’m hoping that some of you developers may be able to help me us fix this. Until then, those of you who need this functionality should be able to use the X11 package from Tiger instead. (Yes, I know you can’t officially download that from — I would like to see that change and am working on making that happen; no ETA. You may be able to find a copy of it lying around somewhere.)

Do not start from the Dock. It will do strange things — you’ll get two icons. This is due to the aforementioned “launcher” in /Applications/Utilities/ not being the same as the real server, which is now located at /usr/X11/

I sincerely hope that you all will like the new X server — while it may look the same, it’s based a much more modern codebase, and I hope to be able to facilitate more rapid development on it so that we — the community — can make it the best X server possible, on any platform.

Ben Byer
CoreOS / BSD Technology Group, XDarwin maintainer