rubyでカウンティングセマフォ - Qiitarequire 'monitor' class CountingSemaphore def initialize(count) @count = count @monitor = Monitor.new @zero_cond = @monitor.new_cond end def synchronize @monitor.synchronize do @zero_cond.wait_while{ @count == 0 } @count -= 1 end ret = yield @monitor.synchronize do @count += 1 @zero_cond.broadcast end ret end end
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