R's DYLD_LIBRARY_PATH override problems on Mac OS X

In Mac OS X native version: The R shell wrapper (bin/R) overrides  
default library search path with DYLD_LIBRARY_PATH and adds (among  
others) /usr/X11R6/lib. This causes problems when modules need  
(directly or indirectly) libraries from Apple's frameworks which are  
masked by X11. Examples for such packages are SJava and RGL. SJava  
needs JavaVM which in turn loads OpenGL framework. RGL needs the  
OpenGL framework directly. The problem is that specifying  
/usr/X11R6/lib in DYLD_LIBRARY_PATH forces the libGL to be loaded from  
the X11 directory instead of the OpenGL framework library. This  
crashes R due to missing symbols, since the modules must link to the  
OpenGL framework. In fact the OpenGL framework libraries load the X11  
libraries internally (but not vice versa) - that's why the default  
load path is frameworks first then X11.

Currently a workaround is to remove /usr/X11R6/lib in R from the  
environment variable prior to loading those packages, but more general  
solution would be better imho. Is the /usr/X11R6/lib really necessary  
in the DYLD_LIBRARY_PATH for some older OS X versions? At least for OS  
X 10.2 with Apple's X11 it is not necessary since X11 is already in  
the default load path.
Btw: the situation didn't crash R in OS X 10.1 (you could load libGL  
from X11 instead of the framework). To analyze the situation: by  
setting DYLD_PRINT_LIBRARIES=1 you can see exactly the sequence of  
loaded libraries and their locations.

 Cheers,
 Simon

	  _
 platform powerpc-apple-darwin6.6
 arch powerpc
 os darwin6.6
 system powerpc, darwin6.6
 status Patched
 major 1
 minor 7.0
 year 2003
 month 05
 day 15
 language R

---
Simon Urbanek
Department of computer oriented statistics and data analysis
University of Augsburg
Universit?tsstr. 14
86135 Augsburg
Germany

Tel: +49-821-598-2236
Fax: +49-821-598-2280

Simon.Urbanek@Math.Uni-Augsburg.de
http://simon.urbanek.info