File Not Found : getopt.h, getopt.c

[baejaeho18]

When I build the darknet_no_gpu.sln, the solution occurs an error which could not find getopt.c and getopt.h.
src/darkunistd.h calls the getopt.h module.
When I build the solution after removing those from the /src/darkunistd.h and /build/darknet/darknet_no_gppu.vcxproj, it successfully works.
I still wonder why does those file doesn't exist.

Thanks!!