%p locale's AM or PM
%r time, 12-hour (hh:mm:ss [AP]M)
%R time, 24-hour (hh:mm)
- %s time in seconds since 00:00:00, Jan 1, 1970 (a nonstandard extension)
+ %s time in seconds since 00:00:00, Jan 1, 1970 (a nonstandard extension)
%S second (00..61)
%T time, 24-hour (hh:mm:ss)
%X locale's time representation (%H:%M:%S)