With this function you can check two dates and times to see which one has the time component earlier or later than the other. The function returns -1 if datetime1 is earlier, 1 if datetime1 is later and 0 if they are the same, and it ignores the date, so literally just which of the times is further through its given day.
|datetime1||The first datetime.|
|datetime2||The datetime to compare the first one to.|
d = date_compare_time(date_create_datetime( 2011, 9, 15, 11, 4, 0 ), date_current_datetime());
This would set "d" to the corresponding value depending on which of the times was the earliest. Basically, if the current time is later than 11:04 am, it would return 1. If earlier, -1. If the time is 11:04, it would return 0.