}
			defer pr1.Close()
			defer pw1.Close()

			pr2, pw2, err := Pipe()
			if err != nil {
				t.Fatal(err)
			}
			defer pr2.Close()
			defer pw2.Close()

			// The pipe is empty, and PIPE_BUF is large enough
			// for this, by (POSIX) definition, so there is no
			// need for an additional goroutine.
			data := []byte("hello")
			if _, err := pw1.Write(data); err != nil {
				t.Fatal(err)
			}