打印格式化printf
#define _DEBUG_
#ifdef _DEBUG_
#define printm(fmt, ...) do { printf("%s line %d, "fmt, __func__, \
__LINE__, ##__VA_ARGS__); } while(0)
#else
#define printm(fmt, ...) do { } while(0)
#endif
#define _DEBUG_
#ifdef _DEBUG_
#define printm(fmt, ...) do { printf("%s line %d, "fmt, __func__, \
__LINE__, ##__VA_ARGS__); } while(0)
#else
#define printm(fmt, ...) do { } while(0)
#endif