(PHP 5.5.0, PECL >= 3.0.0a1)
IntlCalendar::getWeekendTransition — Get time of the day at which weekend begins or ends
Object oriented style
$dayOfWeek
   )Procedural style
Returns the number of milliseconds after midnight at which the weekend begins or ends.
   This is only applicable for days of the week for which
   IntlCalendar::getDayOfWeekType() returns either
   IntlCalendar::DOW_TYPE_WEEKEND_OFFSET or
   IntlCalendar::DOW_TYPE_WEEKEND_CEASE. Calling this
   function for other days of the week is an error condition.
  
This function requires ICU 4.4 or later.
calThe IntlCalendar resource.
dayOfWeek
      One of the constants IntlCalendar::DOW_SUNDAY,
      IntlCalendar::DOW_MONDAY, …,
      IntlCalendar::DOW_SATURDAY.
     
   The number of milliseconds into the day at which the weekend begins or
   ends or FALSE on failure.
  
See example on IntlCalendar::getDayOfWeekType().