In your makefile, you have to add these two libraries.
Exemple for makefile:
LDFLAGS = -lwindom -lgem -lldg
In your source code, you just have to include the windom header :
#include <windom.h>
Please note that gemlib headers are automatically included by the windom header files, so you don't have to explicitly include gem.h or gemx.h.
Note for other compilers:
for GCC2.81, sozobon and purec, gemlib 0.43.6+ is required (a function added in gemlib 0.43.5 is missing for other compilers than gcc -- this has been fixed in gemlib 0.43.6).
example for pure c project with LDG and GEMLIB libraries:
;; Pure C projet file (standard) windom.lib gem.lib ldg.lib pcstdlib.lib pctoslib.lib
link libc instead of ilibc (===> sozobonx) (TODO)
stack size set to 32k