1 #include "stdio.h" 2 #ifdef CMAKE_HAS_X 3 4 # include <X11/Xlib.h> 5 # include <X11/Xutil.h> 6 main()7 int main() 8 { 9 printf("There is X on this computer\n"); 10 return 0; 11 } 12 13 #else 14 main()15 int main() 16 { 17 printf("No X on this computer\n"); 18 return 0; 19 } 20 21 #endif 22