This section describes facilities for keeping track of calendar time. See Time Basics.
The GNU C Library represents calendar time three ways:
time_tdata type) is a compact representation, typically giving the number of seconds of elapsed time since some implementation-specific base time.
struct timevaldata type, which includes fractions of a second. Use this time representation instead of simple time when you need greater precision.
struct tmdata type) represents a calendar time as a set of components specifying the year, month, and so on in the Gregorian calendar, for a specific time zone. This calendar time representation is usually used only to communicate with people.
|• Simple Calendar Time||Facilities for manipulating calendar time.|
|• High-Resolution Calendar||A time representation with greater precision.|
|• Broken-down Time||Facilities for manipulating local time.|
|• High Accuracy Clock||Maintaining a high accuracy system clock.|
|• Formatting Calendar Time||Converting times to strings.|
|• Parsing Date and Time||Convert textual time and date information back into broken-down time values.|
|• TZ Variable||How users specify the time zone.|
|• Time Zone Functions||Functions to examine or specify the time zone.|
|• Time Functions Example||An example program showing use of some of the time functions.|