visus
/
toolchain-gcc-arm-embedded

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>fgetwc (The Red Hat newlib C Library)</title>

<meta name="description" content="fgetwc (The Red Hat newlib C Library)">
<meta name="keywords" content="fgetwc (The Red Hat newlib C Library)">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<link href="index.html#Top" rel="start" title="Top">
<link href="Document-Index.html#Document-Index" rel="index" title="Document Index">
<link href="Document-Index.html#SEC_Contents" rel="contents" title="Table of Contents">
<link href="Stdio.html#Stdio" rel="up" title="Stdio">
<link href="fgetws.html#fgetws" rel="next" title="fgetws">
<link href="fgets.html#fgets" rel="prev" title="fgets">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
blockquote.smallquotation {font-size: smaller}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {margin-left: 3.2em}
div.smalldisplay {margin-left: 3.2em}
div.smallexample {margin-left: 3.2em}
div.smalllisp {margin-left: 3.2em}
kbd {font-style: oblique}
pre.display {font-family: inherit}
pre.format {font-family: inherit}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
pre.smalldisplay {font-family: inherit; font-size: smaller}
pre.smallexample {font-size: smaller}
pre.smallformat {font-family: inherit; font-size: smaller}
pre.smalllisp {font-size: smaller}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
-->
</style>


</head>

<body lang="en">
<a name="fgetwc"></a>
<div class="header">
<p>
Next: <a href="fgetws.html#fgetws" accesskey="n" rel="next">fgetws</a>, Previous: <a href="fgets.html#fgets" accesskey="p" rel="prev">fgets</a>, Up: <a href="Stdio.html#Stdio" accesskey="u" rel="up">Stdio</a> &nbsp; [<a href="Document-Index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Document-Index.html#Document-Index" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<a name="fgetwc_002c-getwc_002c-fgetwc_005funlocked_002c-getwc_005funlocked_002d_002d_002dget-a-wide-character-from-a-file-or-stream"></a>
<h3 class="section">4.13 <code>fgetwc</code>, <code>getwc</code>, <code>fgetwc_unlocked</code>, <code>getwc_unlocked</code>&mdash;get a wide character from a file or stream</h3>
<a name="index-fgetwc"></a>
<a name="index-fgetwc_005funlocked"></a>
<a name="index-_005ffgetwc_005fr"></a>
<a name="index-_005ffgetwc_005funlocked_005fr"></a>
<a name="index-getwc"></a>
<a name="index-getwc_005funlocked"></a>
<a name="index-_005fgetwc_005fr"></a>
<a name="index-_005fgetwc_005funlocked_005fr"></a>
<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t fgetwc(FILE *<var>fp</var>);

#define _GNU_SOURCE
#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t fgetwc_unlocked(FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _fgetwc_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _fgetwc_unlocked_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t getwc(FILE *<var>fp</var>);

#define _GNU_SOURCE
#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t getwc_unlocked(FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _getwc_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _getwc_unlocked_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

</pre></div>
<p><strong>Description</strong><br>
Use <code>fgetwc</code> to get the next wide character from the file or stream
identified by <var>fp</var>.  As a side effect, <code>fgetwc</code> advances the file&rsquo;s
current position indicator.
</p>
<p><code>fgetwc_unlocked</code> is a non-thread-safe version of <code>fgetwc</code>.
<code>fgetwc_unlocked</code> may only safely be used within a scope
protected by flockfile() (or ftrylockfile()) and funlockfile().  This
function may safely be used in a multi-threaded program if and only
if they are called while the invoking thread owns the (FILE *)
object, as is the case after a successful call to the flockfile() or
ftrylockfile() functions.  If threads are disabled, then
<code>fgetwc_unlocked</code> is equivalent to <code>fgetwc</code>.
</p>
<p>The <code>getwc</code> and <code>getwc_unlocked</code> functions or macros functions identically
to <code>fgetwc</code> and <code>fgetwc_unlocked</code>.  It may be implemented as a macro, and
may evaluate its argument more than once. There is no reason ever to use it.
</p>
<p><code>_fgetwc_r</code>, <code>_getwc_r</code>, <code>_fgetwc_unlocked_r</code>, and <code>_getwc_unlocked_r</code>
are simply reentrant versions of the above functions that are passed the
additional reentrant structure pointer argument: <var>ptr</var>.
</p>
<br>
<p><strong>Returns</strong><br>
The next wide character cast to <code>wint_t</code>, unless there is no more data,
or the host system reports a read error; in either of these situations,
<code>fgetwc</code> and <code>getwc</code> return <code>WEOF</code>.
</p>
<p>You can distinguish the two situations that cause an <code>EOF</code> result by
using the <code>ferror</code> and <code>feof</code> functions.
</p>
<br>
<p><strong>Portability</strong><br>
<code>fgetwc</code> and <code>getwc</code> are required by C99 and POSIX.1-2001.
</p>
<p><code>fgetwc_unlocked</code> and <code>getwc_unlocked</code> are GNU extensions.
</p>
<br>

<hr>
<div class="header">
<p>
Next: <a href="fgetws.html#fgetws" accesskey="n" rel="next">fgetws</a>, Previous: <a href="fgets.html#fgets" accesskey="p" rel="prev">fgets</a>, Up: <a href="Stdio.html#Stdio" accesskey="u" rel="up">Stdio</a> &nbsp; [<a href="Document-Index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Document-Index.html#Document-Index" title="Index" rel="index">Index</a>]</p>
</div>


</body>
</html>