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  15     </p><p>Stringstreams (defined in the header <code class="code">&lt;sstream&gt;</code>)
  16       are in this author's opinion one of the coolest things since
  17       sliced time.  An example of their use is in the Received Wisdom
  18       section for Sect1 21 (Strings),
  19       <a class="link" href="strings.html#strings.string.Cstring" title="CString (MFC)"> describing how to
  20       format strings</a>.
  21    </p><p>The quick definition is:  they are siblings of ifstream and ofstream,
  22       and they do for <code class="code">std::string</code> what their siblings do for
  23       files.  All that work you put into writing <code class="code">&lt;&lt;</code> and
  24       <code class="code">&gt;&gt;</code> functions for your classes now pays off
  25       <span class="emphasis"><em>again!</em></span>  Need to format a string before passing the string
  26       to a function?  Send your stuff via <code class="code">&lt;&lt;</code> to an
  27       ostringstream.  You've read a string as input and need to parse it?
  28       Initialize an istringstream with that string, and then pull pieces
  29       out of it with <code class="code">&gt;&gt;</code>.  Have a stringstream and need to
  30       get a copy of the string inside?  Just call the <code class="code">str()</code>
  31       member function.
  32    </p><p>This only works if you've written your
  33       <code class="code">&lt;&lt;</code>/<code class="code">&gt;&gt;</code> functions correctly, though,
  34       and correctly means that they take istreams and ostreams as
  35       parameters, not i<span class="emphasis"><em>f</em></span>streams and o<span class="emphasis"><em>f</em></span>streams.  If they
  36       take the latter, then your I/O operators will work fine with
  37       file streams, but with nothing else -- including stringstreams.
  38    </p><p>If you are a user of the strstream classes, you need to update
  39       your code.  You don't have to explicitly append <code class="code">ends</code> to
  40       terminate the C-style character array, you don't have to mess with
  41       "freezing" functions, and you don't have to manage the
  42       memory yourself.  The strstreams have been officially deprecated,
  43       which means that 1) future revisions of the C++ Standard won't
  44       support them, and 2) if you use them, people will laugh at you.
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