t.Errorf("Got %d bytes; want %d", buf.Len(), sendSize)
	}

	for err := range errc {
		t.Error(err)
	}
}

// Test that sendfile doesn't put a pipe into blocking mode.
func TestSendfilePipe(t *testing.T) {
	switch runtime.GOOS {
	case "plan9", "windows", "js", "wasip1":
		// These systems don't support deadlines on pipes.
		t.Skipf("skipping on %s", runtime.GOOS)
	}

	t.Parallel()