//on Mac OS X
NSLog(@"MAC: %d", TARGET_OS_MAC);
NSLog(@"IOS: %d", TARGET_OS_IPHONE);
NSLog(@"SIM: %d", TARGET_OS_IPHONE_SIMULATOR);

/* expected/got:
MAC: 1
IOS: 0
SIM: 0
*/

//on iPhone Simulator
NSLog(@"MAC: %d", TARGET_OS_MAC);
NSLog(@"IOS: %d", TARGET_OS_IPHONE);
NSLog(@"SIM: %d", TARGET_OS_IPHONE_SIMULATOR);

/* got:
MAC: 1
IOS: 1
SIM: 1
*/

/* expected:
MAC: 0
IOS: 0
SIM: 1
*/