Linking to Apple's X11

[David Liontooth]

After uninstalling XFree86 and installing Apple's X11, new packages were
unable to find the X11 include files:

$ sudo port install libmpeg2
--->  Fetching libsdl
--->  Attempting to fetch SDL-1.2.11.tar.gz from
http://www.libsdl.org/release/
--->  Verifying checksum(s) for libsdl
--->  Extracting libsdl
--->  Applying patches to libsdl
--->  Configuring libsdl
--->  Building libsdl with target all
Error: Target com.apple.build returned: shell command " cd
"/opt/local/var/db/dports/build/_opt_local_var_db_dports_sources_rsync.rsync.darwinports.org_dpupdate_dports_devel_libsdl/work/SDL-1.2.11"
&& make all " returned error 2
Command output: ./include/SDL_syswm.h:55:22: error: X11/Xlib.h: No such
file or directory
./include/SDL_syswm.h:56:23: error: X11/Xatom.h: No such file or directory

As a workaround, I did this:

   cd /usr/X11R6/include
   sudo mv X11 X11-bitmaps
   sudo ln -s /Developer/SDKs/MacOSX10.4u.sdk/usr/X11R6/include/X11 X11

This allows libsdl to compile. What is the correct way to do this? Is
there something like a ld.conf file somewhere?

Dave