| @node Timefns |
| @chapter Time Functions (@file{time.h}) |
| |
| This chapter groups functions used either for reporting on time |
| (elapsed, current, or compute time) or to perform calculations based |
| on time. |
| |
| The header file @file{time.h} defines three types. @code{clock_t} and |
| @code{time_t} are both used for representations of time particularly |
| suitable for arithmetic. (In this implementation, quantities of type |
| @code{clock_t} have the highest resolution possible on your machine, |
| and quantities of type @code{time_t} resolve to seconds.) @code{size_t} |
| is also defined if necessary for quantities representing sizes. |
| |
| @file{time.h} also defines the structure @code{tm} for the traditional |
| representation of Gregorian calendar time as a series of numbers, with |
| the following fields: |
| |
| @table @code |
| @item tm_sec |
| Seconds, between 0 and 60 inclusive (60 allows for leap seconds). |
| |
| @item tm_min |
| Minutes, between 0 and 59 inclusive. |
| |
| @item tm_hour |
| Hours, between 0 and 23 inclusive. |
| |
| @item tm_mday |
| Day of the month, between 1 and 31 inclusive. |
| |
| @item tm_mon |
| Month, between 0 (January) and 11 (December). |
| |
| @item tm_year |
| Year (since 1900), can be negative for earlier years. |
| |
| @item tm_wday |
| Day of week, between 0 (Sunday) and 6 (Saturday). |
| |
| @item tm_yday |
| Number of days elapsed since last January 1, between 0 and 365 inclusive. |
| |
| @item tm_isdst |
| Daylight Savings Time flag: positive means DST in effect, zero means DST |
| not in effect, negative means no information about DST is available. |
| Although for mktime(), negative means that it should decide if DST is in |
| effect or not. |
| @end table |
| |
| @menu |
| * asctime:: Format time as string |
| * clock:: Cumulative processor time |
| * ctime:: Convert time to local and format as string |
| * difftime:: Subtract two times |
| * gmtime:: Convert time to UTC (GMT) traditional representation |
| * localtime:: Convert time to local representation |
| * mktime:: Convert time to arithmetic representation |
| * strftime:: Convert date and time to a user-formatted string |
| * time:: Get current calendar time (as single number) |
| * __tz_lock:: Lock time zone global variables |
| * tzset:: Set timezone info |
| @end menu |
| |
| @page |
| @include time/asctime.def |
| |
| @page |
| @include time/clock.def |
| |
| @page |
| @include time/ctime.def |
| |
| @page |
| @include time/difftime.def |
| |
| @page |
| @include time/gmtime.def |
| |
| @page |
| @include time/lcltime.def |
| |
| @page |
| @include time/mktime.def |
| |
| @page |
| @include time/strftime.def |
| |
| @page |
| @include time/time.def |
| |
| @page |
| @include time/tzlock.def |
| |
| @page |
| @include time/tzset.def |