expand_array.rb

require 'libical'

array = MemoryPointer.new(:int,10)
LibIcal.icalrecur_expand_recurrence("FREQ=YEARLY;BYDAY=SU,WE",Time.now.to_i,10,array)
times = array.read_array_of_int(10).map {|s| Time.at(s)}

times.each {|s| puts s}

libical.rb

require 'rubygems'
require 'ffi'

module LibIcal
  extend FFI::Library
  ffi_lib "/usr/lib/libical.so"
  #attach_function :icaltime_from_timet_with_zone [:int, :int, :pointer], :pointer
  attach_function :icalrecur_expand_recurrence, [:string, :int, :int, :pointer], :int
end