time.h(3HEAD)                                                         Headers                                                        time.h(3HEAD)

NAME

       time.h, time - time types

SYNOPSIS

       #include <time.h>

DESCRIPTION

       The <time.h> header declares the structure tm, which includes the following members:

       int tm_sec     /* seconds [0,60] */
       int tm_min     /* minutes [0,59] */
       int tm_hour    /* hour [0,23] */
       int tm_mday    /* day of month [1,31] */
       int tm_mon     /* month of year [0,11] */
       int tm_year    /* years since 1900 */
       int tm_wday    /* day of week [0,6] (Sunday =0) */
       int tm_yday    /* day of year [0,365] */
       int tm_isdst   /* daylight savings flag */

       The  value  of  tm_isdst  is positive if Daylight Saving Time is in effect, 0 if Daylight Saving Time is not in effect, and negative if the
       information is not available.

       The <time.h> header defines the following symbolic names:

       NULL

           Null pointer constant.

       CLOCKS_PER_SEC

           A number used to convert the value returned by the clock() function into seconds. See clock(3C).

       CLOCK_PROCESS_CPUTIME_ID

           The identifier of the CPU-time clock associated with the process making a clock() or timer*() function call.

       CLOCK_THREAD_CPUTIME_ID

           The identifier of the CPU-time clock associated with the thread making a clock() or timer*() function call.

       The <time.h> header declares the timespec structure, which has the following members:

       time_t tv_sec     /* seconds */
       long   tv_nsec     /* nanoseconds */

       The <time.h> header declares the itimerspec structure, which has the following members:

       struct timespec it_interval     /* timer period */
       struct timespec it_value     /* timer expiration */

       The following manifest constants are defined:

       CLOCK_REALTIME          The identifier of the system-wide realtime clock.

       TIMER_ABSTIME           Flag indicating time is absolute. For functions taking timer objects, this refers to the clock associated with  the
                               timer.

       CLOCK_MONOTONIC         The  identifier  for  the  system-wide  monotonic clock, which is defined as a clock whose value cannot be set with
                               clock_settime() and that cannot have backward clock jumps. The  maximum  possible  clock  jump  is  implementation-
                               defined.  See clock_settime(3RT).

       The clock_t, size_t, time_t, clockid_t, and timer_t types are defined as described in <sys/types.h>. See types.h(3HEAD).

       Although  the  value of CLOCKS_PER_SEC is required to be 1 million on all standard-conforming systems, it can be variable on other systems,
       and it should not be assumed that CLOCKS_PER_SEC is a compile-time constant.

       The <time.h> header provides a declaration for getdate_err.

       The following are declared as variables:

       extern int daylight;
       extern long timezone;
       extern char *tzname[];

       Inclusion of the <time.h> header can make visible all symbols from the <signal.h> header.

USAGE

       The range [0,60] for tm_sec allows for the occasional leap second.

       tm_year is a signed value; therefore, years before 1900 can be represented.

       To obtain the number of clock ticks per second returned by  the  times()  function,  applications  should  call  sysconf(_SC_CLK_TCK).  See
       times(2) and sysconf(3C).

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       +-----------------------------+-----------------------------+
       |Interface Stability          |Standard                     |
       +-----------------------------+-----------------------------+

SEE ALSO

       time(2),  utime(2),  clock(3C),  ctime(3C),  difftime(3C),  getdate(3C), mktime(3C), strftime(3C), strptime(3C), types.h(3HEAD), clock_set-
       time(3RT), nanosleep(3RT), timer_create(3RT), timer_delete(3RT), timer_settime(3RT), attributes(5), standards(5)

SunOS 5.10                                                          10 Sep 2004                                                      time.h(3HEAD)