Introduce DDK headers needed for Virtual Device Drivers development. nt_vdd.h and vddsvc.h will get populated with functions as soon as they will be implemented in NTVDM.
isvbop.h/.inc is fully implemented. isvbop.inc defines 3rd-party VDD bops and "function"-calls for 16-bit apps (in assembler), and isvbop.h defines the same in C-language.
They are both MSVC and GCC-compatible.
svn path=/branches/ntvdm/; revision=61352
