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<h3 class="section">6.3 Restartable Multibyte Conversion Functions</h3>

<p>The ISO&nbsp;C<!-- /@w --> standard defines functions to convert strings from a
multibyte representation to wide character strings.  There are a number
of peculiarities:

     <ul>
<li>The character set assumed for the multibyte encoding is not specified
as an argument to the functions.  Instead the character set specified by
the <code>LC_CTYPE</code> category of the current locale is used; see
<a href="Locale-Categories.html#Locale-Categories">Locale Categories</a>.

     <li>The functions handling more than one character at a time require NUL
terminated strings as the argument (i.e., converting blocks of text
does not work unless one can add a NUL byte at an appropriate place). 
The GNU C library contains some extensions to the standard that allow
specifying a size, but basically they also expect terminated strings. 
</ul>

   <p>Despite these limitations the ISO&nbsp;C<!-- /@w --> functions can be used in many
contexts.  In graphical user interfaces, for instance, it is not
uncommon to have functions that require text to be displayed in a wide
character string if the text is not simple ASCII.  The text itself might
come from a file with translations and the user should decide about the
current locale, which determines the translation and therefore also the
external encoding used.  In such a situation (and many others) the
functions described here are perfect.  If more freedom while performing
the conversion is necessary take a look at the <code>iconv</code> functions
(see <a href="Generic-Charset-Conversion.html#Generic-Charset-Conversion">Generic Charset Conversion</a>).

<ul class="menu">
<li><a accesskey="1" href="Selecting-the-Conversion.html#Selecting-the-Conversion">Selecting the Conversion</a>:      Selecting the conversion and its properties. 
<li><a accesskey="2" href="Keeping-the-state.html#Keeping-the-state">Keeping the state</a>:             Representing the state of the conversion. 
<li><a accesskey="3" href="Converting-a-Character.html#Converting-a-Character">Converting a Character</a>:        Converting Single Characters. 
<li><a accesskey="4" href="Converting-Strings.html#Converting-Strings">Converting Strings</a>:            Converting Multibyte and Wide Character
                                  Strings. 
<li><a accesskey="5" href="Multibyte-Conversion-Example.html#Multibyte-Conversion-Example">Multibyte Conversion Example</a>:  A Complete Multibyte Conversion Example. 
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