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diff --git a/man0p/time.h.0p b/man0p/time.h.0p new file mode 100644 index 000000000..23ec48204 --- /dev/null +++ b/man0p/time.h.0p @@ -0,0 +1,244 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "<time.h>" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" <time.h> +.SH NAME +time.h \- time types +.SH SYNOPSIS +.LP +\fB#include <time.h>\fP +.SH DESCRIPTION +.LP +Some of the functionality described on this reference page extends +the ISO\ C standard. Applications shall define +the appropriate feature test macro (see the System Interfaces volume +of IEEE\ Std\ 1003.1-2001, Section 2.2, The Compilation Environment) +to enable the visibility of these symbols in this +header. +.LP +The \fI<time.h>\fP header shall declare the structure \fBtm\fP, which +shall include at least the following members: +.sp +.RS +.nf + +\fBint tm_sec \fP Seconds [0,60]. \fB +int tm_min \fP Minutes [0,59]. \fB +int tm_hour \fP Hour [0,23]. \fB +int tm_mday \fP Day of month [1,31]. \fB +int tm_mon \fP Month of year [0,11]. \fB +int tm_year \fP Years since 1900. \fB +int tm_wday \fP Day of week [0,6] (Sunday =0). \fB +int tm_yday \fP Day of year [0,365]. \fB +int tm_isdst\fP Daylight Savings flag. \fB +\fP +.fi +.RE +.LP +The value of \fItm_isdst\fP shall be positive if Daylight Savings +Time is in effect, 0 if Daylight Savings Time is not in +effect, and negative if the information is not available. +.LP +The \fI<time.h>\fP header shall define the following symbolic names: +.TP 7 +NULL +Null pointer constant. +.TP 7 +CLOCKS_PER_SEC +A number used to convert the value returned by the \fIclock\fP() function +into +seconds. +.TP 7 +CLOCK_PROCESS_CPUTIME_ID +.sp +The identifier of the CPU-time clock associated with the process making +a \fIclock\fP() or +\fItimer*\fP() function call. +.TP 7 +CLOCK_THREAD_CPUTIME_ID +.sp +The identifier of the CPU-time clock associated with the thread making +a \fIclock\fP() or \fItimer*\fP() function call. +.sp +.LP +The \fI<time.h>\fP header shall declare the structure \fBtimespec\fP, +which has at least the following members: +.sp +.RS +.nf + +\fBtime_t tv_sec \fP Seconds. \fB +long tv_nsec \fP Nanoseconds. \fB +\fP +.fi +.RE +.LP +The \fI<time.h>\fP header shall also declare the \fBitimerspec\fP +structure, which has at least the following +members: +.sp +.RS +.nf + +\fBstruct timespec it_interval \fP Timer period. \fB +struct timespec it_value \fP Timer expiration. \fB +\fP +.fi +.RE +.LP +The following manifest constants shall be defined: +.TP 7 +CLOCK_REALTIME +The identifier of the system-wide realtime clock. +.TP 7 +TIMER_ABSTIME +Flag indicating time is absolute. For functions taking timer objects, +this refers to the clock associated with the timer. +.TP 7 +CLOCK_MONOTONIC +.sp +The identifier for the system-wide monotonic clock, which is defined +as a clock whose value cannot be set via \fIclock_settime\fP() and +which cannot have backward clock jumps. The maximum possible clock +jump shall be implementation-defined. +.sp +.LP +The \fBclock_t\fP, \fBsize_t\fP, \fBtime_t\fP, \fBclockid_t\fP, +and \fBtimer_t\fP types shall be defined as described in \fI<sys/types.h>\fP +\&. +.LP +Although the value of CLOCKS_PER_SEC is required to be 1 million on +all XSI-conformant systems, it may be variable on other +systems, and it should not be assumed that CLOCKS_PER_SEC is a compile-time +constant. +.LP +The \fI<time.h>\fP header shall provide a declaration for \fIgetdate_err\fP. +.LP +The following shall be declared as functions and may also be defined +as macros. Function prototypes shall be provided. +.sp +.RS +.nf + +\fBchar *asctime(const struct tm *); + +char *asctime_r(const struct tm *restrict, char *restrict); + +clock_t clock(void); + +int clock_getcpuclockid(pid_t, clockid_t *); + + +int clock_getres(clockid_t, struct timespec *); +int clock_gettime(clockid_t, struct timespec *); + + +int clock_nanosleep(clockid_t, int, const struct timespec *, + struct timespec *); + + +int clock_settime(clockid_t, const struct timespec *); + +char *ctime(const time_t *); + +char *ctime_r(const time_t *, char *); + +double difftime(time_t, time_t); + +struct tm *getdate(const char *); + +struct tm *gmtime(const time_t *); + +struct tm *gmtime_r(const time_t *restrict, struct tm *restrict); + +struct tm *localtime(const time_t *); + +struct tm *localtime_r(const time_t *restrict, struct tm *restrict); + +time_t mktime(struct tm *); + +int nanosleep(const struct timespec *, struct timespec *); + +size_t strftime(char *restrict, size_t, const char *restrict, + const struct tm *restrict); + +char *strptime(const char *restrict, const char *restrict, + struct tm *restrict); + +time_t time(time_t *); + +int timer_create(clockid_t, struct sigevent *restrict, + timer_t *restrict); +int timer_delete(timer_t); +int timer_gettime(timer_t, struct itimerspec *); +int timer_getoverrun(timer_t); +int timer_settime(timer_t, int, const struct itimerspec *restrict, + struct itimerspec *restrict); + + +void tzset(void); + +\fP +.fi +.RE +.sp +.LP +The following shall be declared as variables: +.sp +.RS +.nf + +\fB +extern int daylight; +extern long timezone; + + +extern char *tzname[]; + +\fP +.fi +.RE +.LP +Inclusion of the \fI<time.h>\fP header may make visible all symbols +from the \fI<signal.h>\fP header. +.LP +\fIThe following sections are informative.\fP +.SH APPLICATION USAGE +.LP +The range [0,60] for \fItm_sec\fP allows for the occasional leap second. +.LP +\fItm_year\fP is a signed value; therefore, years before 1900 may +be represented. +.LP +To obtain the number of clock ticks per second returned by the \fItimes\fP() +function, +applications should call \fIsysconf\fP(_SC_CLK_TCK). +.SH RATIONALE +.LP +The range [0,60] seconds allows for positive or negative leap seconds. +The formal definition of UTC does not permit double leap +seconds, so all mention of double leap seconds has been removed, and +the range shortened from the former [0,61] seconds seen in +previous versions of POSIX. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fI<signal.h>\fP , \fI<sys/types.h>\fP , the System +Interfaces volume of IEEE\ Std\ 1003.1-2001, \fIasctime\fP(), \fIclock\fP(), +\fIclock_getcpuclockid\fP(), \fIclock_getres\fP(), \fIclock_nanosleep\fP(), +\fIctime\fP(), \fIdifftime\fP(), \fIgetdate\fP(), \fIgmtime\fP(), +\fIlocaltime\fP(), \fImktime\fP(), \fInanosleep\fP(), \fIstrftime\fP(), +\fIstrptime\fP(), \fIsysconf\fP(), \fItime\fP(), \fItimer_create\fP(), +\fItimer_delete\fP(), \fItimer_getoverrun\fP(), \fItzname\fP, \fItzset\fP(), +\fIutime\fP() +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . |