cmake HAVE_FOPEN examples

nih-at/libzip cmake-compat/CheckSymbolExists.cmake :58

check_symbol_exists(fopen "stdio.h" HAVE_FOPEN)

flyinghead/flycast core/deps/libzip/cmake-compat/CheckSymbolExists.cmake :58

check_symbol_exists(fopen "stdio.h" HAVE_FOPEN)

omnigres/omnigres cmake/CheckSymbolExists.cmake :65

check_symbol_exists(fopen "stdio.h" HAVE_FOPEN)