Tanner's L-Edit manual has a 6 page appendix on the syntax (in BNF) and
semantics for the GDS II which they support; it is a subset of Calma's Release
3.0.

--Chris Levey
  Solid State Microengineering Lab
  Thayer School, Dartmouth College
  email: chris.levey@Dartmouth.EDU
  http://hypatia.dartmouth.edu/levey.html