title: Default positioning of fill characters for streams
body: <p>On the reference page for <a href="https://en.cppreference.com/w/cpp/io/manip/setfill" rel="nofollow noreferrer"><code>std::setfill</code></a>, there is an example similar to the following program:</p>
  <pre class="lang-cpp prettyprint-override"><code>#include &lt;iostream&gt;
  #include &lt;iomanip&gt;
  int main()
  {
      std::cout &lt;&lt; std::setfill('*') &lt;&lt; std::setw(10) &lt;&lt; 42 &lt;&lt; '\n';
  }
  </code></pre>
  <p>which claims that it should print:</p>
  <pre><code>********42
  </code></pre>
  <p>This suggests that the default positioning of the fill characters is as if the <a href="https://en.cppreference.com/w/cpp/io/manip/left" rel="nofollow noreferrer"><code>std::right</code></a> manipulator was used.</p>
  <p>Does the standard guarantee that this is the behavior, or do I need to specify <code>std::right</code> to be sure?</p>
  <p>Also, does this work for just <code>std::cout</code>, or is it the same for any output stream?</p>