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<pre>
<a name="do-out">
Method             do_out()</a>

Access             Protected

Classification     Modifier

Syntax             virtual result do_out(stateT& state, 
                                         const internT* from, 
                                         const internT* from_end,
                                         const internT*& from_next, 
                                         externT* to, externT* to_limit,
                                         externT*& to_next) const;

Parameters         <em>state</em> is unspecified.

                   <em>from</em> is the beginning of the source character 
                   sequence.

                   <em>from_end</em> is the end of the source character 
                   sequence.

                   <em>from_next</em> points to character in the source 
                   sequence.

                   <em>to</em> is the beginning of the destination sequence.

                   <em>to_limit</em> is the end of the destination sequence.

                   to_next points to character in the destination sequence.

Return Type        <a href="codecvt.htm#Table1">result</a>

</pre>

<h3>Description</h3>
<p>
The do_out() method translates the sequence at [from,from_end)
to a destination sequence stored at [to, to_limit). It translates no more than
(from_end - from) source character elements and stores no more than (to_limit - to)
destination character elements. The method will stop when it encounters
a character in the source sequence that it cannot convert. The <em>from_next</em> and <em>to_next</em>
pointers will point one beyond the last element that was successfully translated.<br>
<br>

If no translation takes place then the method will return <em>noconv</em>. The
pointer <em>to_next</em> will be equal to the argument <em>to</em> and the pointer <em>from_next</em> will
be equal to the argument <em>from</em>. If only some of the characters are translated then
the method will return <em>partial</em>. If <em>from_next</em> == <em>from_end</em> then either
the destination character sequence has not taken in all of the available
destination character elements or that additional source character elements
are required before any another destination character elements can be produced.
</p>
<hr>
<pre>
<a name="do-unshift">
Method             do_unshift()</a>

Access             Protected

Classification     Modifier

Syntax             virtual result do_unshift(stateT& state, externT* to, 
                                             externT* to_limit, 
                                             externT*& to_next) const;

Parameters         <em>state</em> reveals the current state.

                   <em>to</em> is the starting position where the results are 
                   sequentially placed.

                   <em>to_limit</em> is used to determine the number of 
                   characters that are to be stored.

                   <em>to_next</em> points to one beyond the last element if 
                   conversion is successful.

Return Type        <a href="codecvt.htm#Table2">result</a>
             
</pre>
<h3>Description</h3>
<p>
The do_unshift() method places characters starting at <em>to</em> that should be appended to termintate
a sequence when the current stateT is given by the argument <em>state</em>. The method returns the
enumerated value <em>error</em>, <em>noconv</em>, <em>ok</em> or <em>partial</em>.
</p>
<hr>
<pre>
<a name="in">
Method             in()</a>

Access             Public

Classification     Modifier

Syntax             virtual result in(stateT& state, 
                                     const internT* from, 
                                     const internT* from_end,
                                     const internT*& from_next, 
                                     externT* to, externT* to_limit,
                                     externT*& to_next) const;

Parameters         <em>state</em> is unspecified. It can be used to shift 
                   state, to specify conversion options, or used to 
                   identify  cache of seek offsets.

                   <em>from</em> is the beginning of the source character 
                   sequence.

                   <em>from_end</em> is the end of the source character 
                   sequence.

                   <em>from_next</em> points to character in the source 
                   sequence.

                   <em>to</em> is the beginning of the destination sequence.

                   <em>to_limit</em> is the end of the destination sequence.

                   <em>to_next</em> points to character in the destination 
                   sequence.

Return Type        <a href="codecvt.htm#Table1">result</a>

</pre>
<h3>Description</h3>
<p>
The in() method returns do_in(state, from, from_end, from_next, to, to_limit, to_next).
</p>
<hr>
<pre>
<a name="length">
Method             length()</a>

Access             Public

Classification     Accessor

Syntax             int length(const stateT& state, const externT* from, 
                              const externT* end, size_t max) const;

Parameters         <em>state</em> is initialized either for the beginning of 
                   a sequence or equal to the result of the previous 
                   conversion of the sequence.

                   <em>from</em> is the beginning of the character sequence.

                   <em>end</em> is the end of the character sequence.

                   <em>max</em> is maximum value of internT characters available 
                   in the specified range.

Return             This method returns the number max or fewer internT 
                   characters.

</pre>

<h3>Description</h3>
<p>
The length() method returns do_length(state, from, end, max).
</p>
<hr>
<pre>
<a name="encoding">
Method             encoding()</a>

Access             Public

Classification     Accessor

Syntax             int encoding() const throw();

Parameters         None

Return             This method returns the constant number of externT 
                   characters needed to produce an internal character.

</pre>

<h3>Description</h3>
<p>
The encoding() method returns do_encoding().
</p>
<hr>
<pre>
<a name="max-length">
Method             max_length()</a>

Access             Public

Classification     Accessor

Syntax             int max_length() const throw();

Parameters         None

Return             This method returns the maximum value that 
                   do_length() can return.

</pre>

<h3>Description</h3>
<p>
The max_length() method returns do_max_length().
</p>
<hr>
<pre>
<a name="out">
Method             out()</a>

Access             Public

Classification     Modifier

Syntax             result out(stateT& state, const internT* from, 
                              const intern* from_end,
                              const internT*& from_next, 
                              externT* to, extern* to_limit, 
                              externT*& to_next);

Parameters         <em>state</em> is unspecified. It can be used to shift 
                   state, to specify conversion options, or used to 
                   identify  cache of seek offsets.

                   <em>from</em> is the beginning of the source range.

                   <em>from_end</em> is the end of the source range.

                   <em>from_next</em> points to one beyond the last element 
                   if conversion is successful.

                   <em>to</em> is the starting position where the results are 
                   sequentially placed.

                   <em>to_limit</em> is used to determine the number of 
                   characters that are to be stored.

                   <em>to_next</em> points to one beyond the last element if 
                   conversion is successful.

Return Type        <a href="codecvt.htm#Table1">result</a>             
</pre>

<h3>Description</h3>
<p>
The out() method returns do_out(state, from, from_end, from_next, to, to_limit, to_next).
</p>
<hr>
<pre>
<a name="unshift">
Method             unshift()</a>

Access             Public

Classification     Modifier

Syntax             result unshift(stateT state&, externT* to, 
                                  externT* to_limit, 
                                  externT*& to_next) const;

Parameters         <em>state</em> reveals the current state.

                   <em>to</em> is the starting position where the results are 
                   sequentially placed.

                   <em>to_limit</em> is used to determine the number of 
                   characters that are to be stored.

                   <em>to_next</em> points to one beyond the last element if 
                   conversion is successful.


Return Type        <a href="codecvt.htm#Table2">result</a>

</pre>

<h3>Description</h3>
<p>
The unshift() method returns do_unshift(state, to, to_limit, to_next).
</p>

<hr>
<a name="Table1"><h4>TABLE 1:</h4></a>
<p>
The result values are:
</p>
<hr>
<pre>
     <b>Value</b>         <b>Meaning</b>

     ok            The conversion was completed

     partial       Not all of the source characters were converted.

     error         A from_type character was encountered and could
                   not be converted.

     noconv        No conversion was needed.
</pre>
<hr>

<a name="Table2"><h4>TABLE 2:</h4></a>
<p>
The result values are:
</p>
<hr>
<pre>
     <b>Value</b>         <b>Meaning</b>

     ok            The sequence was completed

     partial       More characters are needed to complete termination.

     error         <em>state</em> has an invalid value.

     noconv        For this <em>state_type</em>, no termination is needed.
</pre>
<hr>
<a name="crd"><h2>The Class Relationship Diagram for codecvt</h2></a>
<img src="codecvt.gif">
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