如何知道当前架构是mac中的i386还是x86_64？(Xcode中)

Question

我正在处理一个在不同架构中需要不同参数的相机,是否有一个标志我可以检查我的mac是32位还是64位？我试过这个但似乎不起作用,我总是得到32位!:

#if defined(PER_ARCH_CFLAGS_x86_64)
    NSLog(@"64bit!!");
#else 
    NSLog(@"32Bits!!");
#endif  

Answer 1

#ifdef __x86_64__
  //64-bit intel
#endif
#ifdef __i386__
  //32-bit intel
#endif
//carry on for ppc, ppc64, ARM

要么...

#ifdef __LP64__
  //64-bit Intel or PPC
#else
  //32-bit Intel, PPC or ARM
#endif

Answer 2

#ifdef __LP64__
// 64-bit code
#else
// 32-bit code
#endif

来源:http://developer.apple.com/mac/library/documentation/Darwin/Conceptual/64bitPorting/MakingCode64-BitClean/MakingCode64-BitClean.html#//apple_ref/doc/uid/TP40001064-CH226-SW2