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
is a null pointer, no value is stored.
Upon successful completion,
returns the value of time.
Otherwise a value of
is returned and the global variable
is set to indicate the error.
function appeared in
Version 2 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.
Version 6 AT&T UNIX,
scale was changed to seconds, extending the pre-crisis stagnation
period up to a total of 68 years.