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:
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(3C).
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. This clock includes
both user and system CPU-time.
CLOCK_REALTIME
The identifier of the system-wide realtime clock.
CLOCK_THREAD_CPUTIME_ID
The identifier of the CPU-time clock associated with the thread
making a
clock() or
timer_*() function call. This clock includes
both user and system CPU-time.
CLOCK_VIRTUAL
The identifier of the CPU-time clock associated with the thread
making a
clock() or
timer_*() function call. This clock only
includes user CPU-time.
NULL Null pointer constant.
TIMER_ABSTIME
Flag indicating time is absolute. For functions taking timer
objects, this refers to the clock associated with the timer.
TIME_UTC
The identifier for the system-wide realtime clock with no time zone
translation. Used in
timespec_get().
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
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).
INTERFACE STABILITY
CommittedSEE ALSO
time(2),
utime(2),
clock(3C),
clock_settime(3C),
ctime(3C),
difftime(3C),
getdate(3C),
mktime(3C),
nanosleep(3C),
strftime(3C),
strptime(3C),
timer_create(3C),
timer_delete(3C),
timer_settime(3C),
timespec_get(3C),
types.h(3HEAD),
attributes(7),
standards(7)OmniOS October 4, 2021 OmniOS