On the use of the Makefiles in this directory:

Makefile: used by "make" command, consists of two parts:

1st part: Path specifications for IDL, Fortran and C libraries, compiler options
	  One of Makefile.Linux.in or Makefile.Darwin.in

2nd part: definition of library locations and compile commands, using
	  one of Makefile.idl.in or Makefile.gdl.in (add. object gdl.c) 
	  Makefile.pro.ina is used for inclusion of proprietary libraries 

Makefile.gdl.in: compiles additional object gdl.c for IDL_TTYReset function 
