include/time.h

   1 /* The <time.h> header is used by the procedures that deal with time.
   2  * Handling time is surprisingly complicated, what with GMT, local time
   3  * and other factors.  Although the Bishop of Ussher (1581-1656) once
   4  * calculated that based on the Bible, the world began on 12 Oct. 4004 BC
   5  * at 9 o'clock in the morning, in the UNIX world time begins at midnight,
   6  * 1 Jan. 1970 GMT.  Before that, all was NULL and (void).
   7  */
   8
   9 #ifndef _TIME_H
  10 #define _TIME_H
  11
  12 #define CLOCKS_PER_SEC    60
  13
  14 #ifdef _POSIX_SOURCE
  15 #define CLK_TCK CLOCKS_PER_SEC  /* obsolescent mame for CLOCKS_PER_SEC */
  16 #endif
  17
  18 #define NULL    ((void *)0)
  19
  20 #ifndef _SIZE_T
  21 #define _SIZE_T
  22 typedef unsigned int size_t;
  23 #endif
  24
  25 #ifndef _TIME_T
  26 #define _TIME_T
  27 typedef long time_t;            /* time in sec since 1 Jan 1970 0000 GMT */
  28 #endif
  29
  30 #ifndef _CLOCK_T
  31 #define _CLOCK_T
  32 typedef long clock_t;           /* time in ticks since process started */
  33 #endif
  34
  35 struct tm {
  36   int tm_sec;                   /* seconds after the minute [0, 59] */
  37   int tm_min;                   /* minutes after the hour [0, 59] */
  38   int tm_hour;                  /* hours since midnight [0, 23] */
  39   int tm_mday;                  /* day of the month [1, 31] */
  40   int tm_mon;                   /* months since January [0, 11] */
  41   int tm_year;                  /* years since 1900 */
  42   int tm_wday;                  /* days since Sunday [0, 6] */
  43   int tm_yday;                  /* days since January 1 [0, 365] */
  44   int tm_isdst;                 /* Daylight Saving Time flag */
  45 };
  46
  47 extern char *tzname[];
  48
  49 /* Function Prototypes. */
  50 #ifndef _ANSI_H
  51 #include <ansi.h>
  52 #endif
  53
  54 _PROTOTYPE( clock_t clock, (void)                                       );
  55 _PROTOTYPE( double difftime, (time_t _time1, time_t _time0)             );
  56 _PROTOTYPE( time_t mktime, (struct tm *_timeptr)                        );
  57 _PROTOTYPE( time_t time, (time_t *_timeptr)                             );
  58 _PROTOTYPE( char *asctime, (const struct tm *_timeptr)                  );
  59 _PROTOTYPE( char *ctime, (const time_t *_timer)                 );
  60 _PROTOTYPE( struct tm *gmtime, (const time_t *_timer)                   );
  61 _PROTOTYPE( struct tm *localtime, (const time_t *_timer)                );
  62 _PROTOTYPE( size_t strftime, (char *_s, size_t _max, const char *_fmt,
  63                                 const struct tm *_timep)                );
  64
  65 #ifdef _POSIX_SOURCE
  66 _PROTOTYPE( void tzset, (void)                                          );
  67 #endif
  68
  69 #ifdef _MINIX
  70 _PROTOTYPE( int stime, (time_t *_top)                                   );
  71 #endif
  72
  73 extern long timezone;
  74
  75 #ifdef _POSIX_SOURCE
  76 struct timespec
  77 {
  78         time_t tv_sec;
  79         long tv_nsec;
  80 };
  81
  82 int nanosleep(const struct timespec *rqtp, struct timespec *rmtp);
  83 #endif
  84
  85 #endif /* _TIME_H */