idlwave-system-directory

idlwave-system-directory is a variable defined in `idlwave.el'.
Its value is

""

Documentation:
The IDL system directory for Windows and MacOS. Not needed under
UNIX. Set this to the value of the `!DIR' system variable in IDL.
IDLWAVE uses this to find out which of the library routines belong to
the official system library. All files inside the `lib' subdirectory
are considered system library files - so don't install private stuff
in this directory. On UNIX systems, IDLWAVE queries the shell for the
value of `!DIR'. See also `idlwave-library-path'.

You can customize this variable.