#import #define MAX_DISPLAYS 8 int main(int argc, const char * argv[]) { const CGGammaValue inverted_gamma[2] = {1, 0}; CGDirectDisplayID active_displays[MAX_DISPLAYS]; uint32_t display_count; CGError error = CGGetActiveDisplayList( MAX_DISPLAYS, &active_displays[0], &display_count ); if (error != kCGErrorSuccess) { return 69; } for (int i = 0; i < display_count; i++) { error = CGSetDisplayTransferByTable( active_displays[i], 2, inverted_gamma, inverted_gamma, inverted_gamma ); if (error != kCGErrorSuccess) { // TODO: error handling } } sleep(4); CGDisplayRestoreColorSyncSettings(); return 0; }