no such file sys/shm.h

So i looked this up and cant really find an answer probably cuz most ppl dont deal with this but im using cygwin and im compiling with
#include <sys/shm.h>
but it cant find the file so i obviously check with cygwin usr/include/sys/ and its in there so im not sure how to make the system find the files thats already there?

Classically, this means that you've installed MinGW or another CygWIN and they are conflicted.

Otherwise, check your environment to see everywhere GCC is looking for the header.

Soma