class Async::HTTP::Body::Pipe

def close 

def close
	@reader&.stop
	@writer&.stop
	
	@tail.close
end

def initialize(input, output = Writable.new, task: Task.current)

If the input stream is closed first, it's likely the output stream will also be closed. 
def initialize(input, output = Writable.new, task: Task.current)
	@input = input
	@output = output
	
	head, tail = IO::Socket.pair(Socket::AF_UNIX, Socket::SOCK_STREAM)
	
	@head = IO::Stream.new(head)
	@tail = tail
	
	@reader = nil
	@writer = nil
	
	task.async(&self.method(:reader))
	task.async(&self.method(:writer))
end

def reader(task)

Read from the @input stream and write to the head of the pipe. 
def reader(task)
	@reader = task
	
	task.annotate "#{self.class} reader."
	
	while chunk = @input.read
		@head.write(chunk)
		@head.flush
	end
	
	@head.close_write
ensure
	@reader = nil
	@input.close($!)
	
	@head.close if @writer.nil?
end

def to_io 

def to_io
	@tail
end

def writer(task)

If the @tail is closed, this will cause chunk to be nil, which in turn will call `@output.close` and `@head.close`
Read from the head of the pipe and write to the @output stream. 
def writer(task)
	@writer = task
	
	task.annotate "#{self.class} writer."
	
	while chunk = @head.read_partial
		@output.write(chunk)
	end
ensure
	@writer = nil
	
	@output.close($!)
	
	@head.close if @reader.nil?
end