#ifdef CMAKE_HAS_X #include #include #include int main() { Display *mydisplay; char* display = ":0"; if ( getenv("DISPLAY") ) { display = getenv("DISPLAY"); } mydisplay=XOpenDisplay(display); if ( mydisplay ) { XCloseDisplay(mydisplay); } return 0; } #else #include "stdio.h" int main() { printf("No X on this computer\n"); return 0; } #endif