thread.h not recognised

[Kate Adams]

hello all, 

im trying to run an old college server program (originally used with unix on sun machines) using cygwin on a pc.
#include <pthread.h> is fine, but it doesnt let me have #include <thread.h>.
if i comment out thread.h then the program runs but it isnt working correctly with the client, can anyone tell me how i can get gcc to be able to include thread.h?

i am a very rusty non-expert so sorry if this is a dumbass question. 
thanks very much, 
kate