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<H2>41.1 User-Defined Character Types</H2>
<A NAME="idx965"><!></A>
<P>One of the fundamental differences between the new, templated iostreams and the traditional iostreams is the ability of the new iostreams to accommodate user-defined character types. It's now possible to use the C++ iostreams interface with arbitrary character-like types, as well as with ordinary <SAMP>char</SAMP>s. </P>
<P>Of course, this flexibility comes at a price. Any user-defined character type must satisfy certain requirements. The type really must act like an ordinary <SAMP>char</SAMP> in most circumstances. In addition, several classes must be defined to support the type in the iostreams environment.</P>
<A NAME="4111"><H3>41.1.1 Requirements for User-Defined Character Types</H3></A>
<A NAME="idx966"><!></A>
<P>In general, user-defined character types must meet the requirements of a POD type:</P>

<UL><PRE>
struct Echar
{
  char c;
  char i;
};

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