Difference between UINT32_C and uint32_t
问题 As far as I know the suffix t in uint32_t denote t ype name but I wonder to know what is the C in UINT32_C and what is the differences? 回答1: UINT32_C is a macro which defines integer constant of type uint_least32_t . For example: UINT32_C(123) // Might expand to 123UL on system where uint_least32_t is unsigned long // or just 123U, if uint_least32_t is unsigned int. 7.20.4.1 Macros for minimum-width integer constants The macro INT N _C( value ) shall expand to an integer constant expression