Apple has migrated its X11 suite (xquartz) to /opt/X11 for the past few OS X major releases, but they have retained some symlinks from /usr/X11 and/or /usr/X11R6 so that we can still access headers and libs via -I/usr/X11/include and similar. A few years ago, they temporarily dropped a symlink, and many things became uncompileable unless one knew to pass --x-includes= and --x-libraries paths. Rumor is they might be doing it again in the next release. If I patch libs.m4 to place /opt/X11/include in the ac_x_header_dirs default search paths list, X11 is detected correctly.
dan -- Daniel Macks dma...@netspace.org
