fstream.h and fstream are (should be) the same header. Write fstream.h yourself:
#pragma once
#ifdef __CPLUSPLUS
#include <fstream>
#else
#error "only for C++"
#endif
Most of compilers do something like this but in opposite fashion :) They have "traditional" headers (like fstream.h) for backward compatibility and redirect "new style" headers (like fstream) to them. You have only a "new style" header and redirect the "traditional" header to it. Everybody who will compile your program and who will have fstream.h should pass.