The only file CLP( 
) system needs to read on startup is init.clpr.
It always looks for this file in the directory specified at runtime by the
environment variable CLPRLIB, defaulting to either the current working
directory or what LIBPATH has been specified as in the Makefile.
The only other environment variable which one may want to change is to add your own list of file suffixes with the environment variable CLPRSUFFIX. The format is in the style of the UNIX sh PATH variable.