libc - Simple Calendar Time
Simple Calendar Time
This section describes the `time_t' data type for representing
calendar time, and the functions which operate on calendar time objects.
These facilities are declared in the header file `time.h'.
- -- Data Type: time_t
- This is the data type used to represent calendar time. In the GNU
C library and other POSIX-compliant implementations, `time_t' is
equivalent to `long int'. When interpreted as an absolute time
value, it represents the number of seconds elapsed since 00:00:00
on January 1, 1970, Coordinated Universal Time. (This date is
sometimes referred to as the "epoch".)
In other systems, `time_t' might be either an integer or
floating-point type.
- --Function: double difftime (time_t TIME1, time_t TIME0)
- The `difftime' function returns the number of seconds elapsed
between time TIME1 and time TIME0, as a value of type `double'.
In the GNU system, you can simply subtract `time_t' values. But on
other systems, the `time_t' data type might use some other encoding
where subtraction doesn't work directly.
- --Function: time_t time (time_t *RESULT)
- The `time' function returns the current time as a value of type
`time_t'. If the argument RESULT is not a null pointer, the time
value is also stored in `*RESULT'. If the calendar time is not
available, the value `(time_t)(-1)' is returned.
converted by gnuinfo
Main page of this Linux-oriented web server
This server is maintained by VH