get time of day
function returns the value of time in seconds since 0 hours, 0 minutes, 0
seconds, January 1, 1970, Coordinated Universal Time (UTC).
A copy of the time value may be saved to the area indicated by the pointer tloc. If tloc is a null pointer, no value is stored.
Upon successful completion,
the value of time. Otherwise a value of (time_t)-1 is
returned and the global variable errno is set to
indicate the error.
The following error codes may be set in errno:
- An argument address referenced invalid memory.
clock_gettime(2), gettimeofday(2), ctime(3)
time() system call first appeared in
Version 1 AT&T UNIX and used to return
time in sixtieths of a second in 32 bits, which was to guarantee a crisis
every 2.26 years. Since Version 6 AT&T
time() scale was changed to seconds,
extending the pre-crisis stagnation period up to a total of 68 years.