將tm結構的值轉(zhuǎn)換為一個time_t類型的值
在32位系統(tǒng)中time_t是一個long。
頭文件 <time.h>

time_t mktime(
   struct tm *timeptr
);
__time32_t _mktime32(
   struct tm *timeptr
);
__time64_t _mktime64(
   struct tm *timeptr
);

獲得系統(tǒng)時間。
頭文件 <time.h>
In Visual C++ 2005, time is a wrapper for _time64 and time_t is, by default, equivalent to __time64_t.
If you need to force the compiler to interpret time_t as the old 32-bit time_t, you can define _USE_32BIT_TIME_T.
This is not recommended because your application may fail after January 18, 2038; the use of this macro is not allowed on 64-bit platforms.

time_t time(
   time_t *timer
);
__time32_t _time32(
   __time32_t *timer
);
__time64_t _time64(
   __time64_t *timer
);


將時間轉(zhuǎn)換成一個字符串
頭文件 <time.h>

char *ctime(
   const time_t *timer
);
char *_ctime32(
   const __time32_t *timer )
;
char *_ctime64(
   const __time64_t *timer )
;
wchar_t *_wctime(
   const time_t *timer
);
wchar_t *_wctime32(
   const __time32_t *timer
);
wchar_t *_wctime64(
   const __time64_t *timer
);

將時間轉(zhuǎn)換成一個字符串
是個安全的版本，用來替代上面的函數(shù)
頭文件 <time.h>

errno_t ctime_s(
   char* buffer,
   size_t sizeInBytes,
   const time_t *time
);
errno_t _ctime32_s(
   char* buffer,
   size_t sizeInBytes,
   const __time32_t *time
);
errno_t _ctime64_s(
   char* buffer,
   size_t sizeInBytes,
   const __time64_t *time )
;
errno_t _wctime_s(
   wchar_t* buffer,
   size_t sizeInWords,
   const time_t *time
);
errno_t _wctime32_s(
   wchar_t* buffer,
   size_t sizeInWords,
   const __time32_t *time
);
errno_t _wctime64_s(
   wchar_t* buffer,
   size_t sizeInWords,
   const __time64_t *time
);
template <size_t size>
errno_t _ctime32_s(
   char (&buffer)[size],
   const __time32_t *time
); // C++ only
template <size_t size>
errno_t _ctime64_s(
   char (&buffer)[size],
   const __time64_t *time
); // C++ only
template <size_t size>
errno_t _wctime32_s(
   wchar_t (&buffer)[size],
   const __time32_t *time
); // C++ only
template <size_t size>
errno_t _wctime64_s(
   wchar_t (&buffer)[size],
   const __time64_t *time
); // C++ only


將時間值轉(zhuǎn)換成一個結構
頭文件 <time.h>

struct tm *gmtime(
   const time_t *timer
);
struct tm *_gmtime32(
   const time32_t *timer
);
struct tm *_gmtime64(
   const __time64_t *timer
);

將時間值轉(zhuǎn)換成一個結構
頭文件 <time.h>
同上面函數(shù)的功能，是安全版本

errno_t _gmtime_s(
   struct tm* _tm,
   const __time_t* time
);
errno_t _gmtime32_s(
   struct tm* _tm,
   const __time32_t* time
);
errno_t _gmtime64_s(
   struct tm* _tm,
   const __time64_t* time
);

將時間轉(zhuǎn)換成本地時間。
頭文件 <time.h>

struct tm *localtime(
   const time_t *timer
);
struct tm *_localtime32(
   const __time32_t *timer
);
struct tm *_localtime64(
   const __time64_t *timer
);

將時間轉(zhuǎn)換成本地時間。
頭文件 <time.h>
同上面函數(shù)的功能，是安全版本

errno_t _localtime_s(
   struct tm* _tm,
   const time_t *time
);
errno_t _localtime32_s(
   struct tm* _tm,
   const time32_t *time
);
errno_t _localtime64_s(
   struct tm* _tm,
   const _time64_t *time
);

clock函數(shù)
頭文件 <time.h>
clock_t clock( void );