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.TH time.h 3HEAD "5 Feb 2008" "SunOS 5.11" "Headers"
.SH NAME
time.h, time \- time types
.SH SYNOPSIS
.LP
.nf
#include <\fBtime.h\fR>
.fi
.SH DESCRIPTION
.sp
.LP
The <\fBtime.h\fR> header declares the structure \fBtm\fR, which includes the following members:
.sp
.in +2
.nf
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 */
.fi
.in -2
.sp
.LP
The value of \fBtm_isdst\fR 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.
.sp
.LP
The <\fBtime.h\fR> header defines the following symbolic names:
.sp
.ne 2
.mk
.na
\fB\fBNULL\fR\fR
.ad
.RS 28n
.rt
Null pointer constant.
.RE
.sp
.ne 2
.mk
.na
\fB\fBCLOCKS_PER_SEC\fR\fR
.ad
.RS 28n
.rt
A number used to convert the value returned by the \fBclock()\fR function into seconds. See \fBclock\fR(3C).
.RE
.sp
.ne 2
.mk
.na
\fB\fBCLOCK_PROCESS_CPUTIME_ID\fR\fR
.ad
.RS 28n
.rt
The identifier of the CPU-time clock associated with the process making a \fBclock()\fR or \fBtimer*()\fR function call.
.RE
.sp
.ne 2
.mk
.na
\fB\fBCLOCK_THREAD_CPUTIME_ID\fR\fR
.ad
.RS 28n
.rt
The identifier of the CPU-time clock associated with the thread making a \fBclock()\fR or \fBtimer*()\fR function call.
.RE
.sp
.LP
The <\fBtime.h\fR> header declares the \fBtimespec\fR structure, which has the following members:
.sp
.in +2
.nf
time_t tv_sec /* seconds */
long tv_nsec /* nanoseconds */
.fi
.in -2
.sp
.LP
The <\fBtime.h\fR> header declares the \fBitimerspec\fR structure, which has the following members:
.sp
.in +2
.nf
struct timespec it_interval /* timer period */
struct timespec it_value /* timer expiration */
.fi
.in -2
.sp
.LP
The following manifest constants are defined:
.sp
.ne 2
.mk
.na
\fB\fBCLOCK_REALTIME\fR\fR
.ad
.RS 19n
.rt
The identifier of the system-wide realtime clock.
.RE
.sp
.ne 2
.mk
.na
\fB\fBTIMER_ABSTIME\fR\fR
.ad
.RS 19n
.rt
Flag indicating time is absolute. For functions taking timer objects, this refers to the clock associated with the timer.
.RE
.sp
.ne 2
.mk
.na
\fB\fBCLOCK_MONOTONIC\fR\fR
.ad
.RS 19n
.rt
The identifier for the system-wide monotonic clock, which is defined as a clock whose value cannot be set with \fBclock_settime()\fR and that cannot have backward clock jumps. The maximum possible clock jump is implementation-defined. See \fBclock_settime\fR(3C).
.RE
.sp
.LP
The \fBclock_t\fR, \fBsize_t\fR, \fBtime_t\fR, \fBclockid_t\fR, and \fBtimer_t\fR types are defined as described in <\fBsys/types.h\fR>. See \fBtypes.h\fR(3HEAD).
.sp
.LP
Although the value of \fBCLOCKS_PER_SEC\fR 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 \fBCLOCKS_PER_SEC\fR is a compile-time constant.
.sp
.LP
The <\fBtime.h\fR> header provides a declaration for \fBgetdate_err\fR.
.sp
.LP
The following are declared as variables:
.sp
.in +2
.nf
extern int daylight;
extern long timezone;
extern char *tzname[];
.fi
.in -2
.sp
.LP
Inclusion of the <\fBtime.h\fR> header can make visible all symbols from the <\fBsignal.h\fR> header.
.SH USAGE
.sp
.LP
The range [0,60] for \fBtm_sec\fR allows for the occasional leap second.
.sp
.LP
\fBtm_year\fR is a signed value; therefore, years before 1900 can be represented.
.sp
.LP
To obtain the number of clock ticks per second returned by the \fBtimes()\fR function, applications should call \fBsysconf(_SC_CLK_TCK)\fR. See \fBtimes\fR(2) and \fBsysconf\fR(3C).
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp
.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i)
lw(2.75i) |lw(2.75i)
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
_
StandardSee \fBstandards\fR(5).
.TE
.SH SEE ALSO
.sp
.LP
\fBtime\fR(2), \fButime\fR(2), \fBclock\fR(3C), \fBctime\fR(3C), \fBdifftime\fR(3C), \fBgetdate\fR(3C), \fBmktime\fR(3C), \fBstrftime\fR(3C), \fBstrptime\fR(3C), \fBtypes.h\fR(3HEAD), \fBclock_settime\fR(3C), \fBnanosleep\fR(3C), \fBtimer_create\fR(3C), \fBtimer_delete\fR(3C), \fBtimer_settime\fR(3C), \fBattributes\fR(5), \fBstandards\fR(5)