}
	}
	return readers, nil
}

func gatherFile(f string) (local.ReaderSource, error) {
	r, err := os.Open(f)
	if err != nil {
		return local.ReaderSource{}, err
	}
	runtime.SetFinalizer(r, func(x *os.File) {
		err = x.Close()
		if err != nil {
			log.Infof("file : %s is not closed: %v", f, err)
		}
	})
	return local.ReaderSource{Name: f, Reader: r}, nil
}

</p>

<h3 id="finalizer">Finalizers</h3>

<p>
The <a href="/pkg/runtime/"><code>runtime</code></a> package provides
a <code>SetFinalizer</code> function that adds a finalizer to be called when
a particular object is no longer reachable by the program.
A call to <code>SetFinalizer(x, f)</code> is synchronized before the finalization call <code>f(x)</code>.
</p>

<h3 id="more">Additional Mechanisms</h3>

<p>