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 </div>

 <h4 class="subsection">12.14.9 Variable Arguments Input Functions</h4>

 <p>The functions <code>vscanf</code> and friends are provided so that you can
 define your own variadic <code>scanf</code>-like functions that make use of
 the same internals as the built-in formatted output functions.
 These functions are analogous to the <code>vprintf</code> series of output
 functions.  See <a href="Variable-Arguments-Output.html#Variable-Arguments-Output">Variable Arguments Output</a>, for important
 information on how to use them.

    <p><strong>Portability Note:</strong> The functions listed in this section were
 introduced in ISO&nbsp;C99<!-- /@w --> and were before available as GNU extensions.

 <!-- stdio.h -->
 <!-- ISO -->
 <div class="defun">
 &mdash; Function: int <b>vscanf</b> (<var>const char *template, va_list ap</var>)<var><a name="index-vscanf-1089"></a></var><br>
 <blockquote><p>This function is similar to <code>scanf</code>, but instead of taking
 a variable number of arguments directly, it takes an argument list
 pointer <var>ap</var> of type <code>va_list</code> (see <a href="Variadic-Functions.html#Variadic-Functions">Variadic Functions</a>).
 </p></blockquote></div>

 <!-- wchar.h -->
 <!-- ISO -->
 <div class="defun">
 &mdash; Function: int <b>vwscanf</b> (<var>const wchar_t *template, va_list ap</var>)<var><a name="index-vwscanf-1090"></a></var><br>
 <blockquote><p>This function is similar to <code>wscanf</code>, but instead of taking
 a variable number of arguments directly, it takes an argument list
 pointer <var>ap</var> of type <code>va_list</code> (see <a href="Variadic-Functions.html#Variadic-Functions">Variadic Functions</a>).
 </p></blockquote></div>

 <!-- stdio.h -->
 <!-- ISO -->
 <div class="defun">
 &mdash; Function: int <b>vfscanf</b> (<var>FILE *stream, const char *template, va_list ap</var>)<var><a name="index-vfscanf-1091"></a></var><br>
 <blockquote><p>This is the equivalent of <code>fscanf</code> with the variable argument list
 specified directly as for <code>vscanf</code>.
 </p></blockquote></div>

 <!-- wchar.h -->
 <!-- ISO -->
 <div class="defun">
 &mdash; Function: int <b>vfwscanf</b> (<var>FILE *stream, const wchar_t *template, va_list ap</var>)<var><a name="index-vfwscanf-1092"></a></var><br>
 <blockquote><p>This is the equivalent of <code>fwscanf</code> with the variable argument list
 specified directly as for <code>vwscanf</code>.
 </p></blockquote></div>

 <!-- stdio.h -->
 <!-- ISO -->
 <div class="defun">
 &mdash; Function: int <b>vsscanf</b> (<var>const char *s, const char *template, va_list ap</var>)<var><a name="index-vsscanf-1093"></a></var><br>
 <blockquote><p>This is the equivalent of <code>sscanf</code> with the variable argument list
 specified directly as for <code>vscanf</code>.
 </p></blockquote></div>

 <!-- wchar.h -->
 <!-- ISO -->
 <div class="defun">
 &mdash; Function: int <b>vswscanf</b> (<var>const wchar_t *s, const wchar_t *template, va_list ap</var>)<var><a name="index-vswscanf-1094"></a></var><br>
 <blockquote><p>This is the equivalent of <code>swscanf</code> with the variable argument list
 specified directly as for <code>vwscanf</code>.
 </p></blockquote></div>

    <p>In GNU C, there is a special construct you can use to let the compiler
 know that a function uses a <code>scanf</code>-style format string.  Then it
 can check the number and types of arguments in each call to the
 function, and warn you when they do not match the format string.
 For details, see <a href="../gcc/Function-Attributes.html#Function-Attributes">Declaring Attributes of Functions</a>.

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	This file documents the GNU C library.

	This is Edition 0.12, last updated 2007-10-27,
	of `The GNU C Library Reference Manual', for version
	2.8 (Sourcery G++ Lite 2011.03-41).

	Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002,
	2003, 2007, 2008, 2010 Free Software Foundation, Inc.

	Permission is granted to copy, distribute and/or modify this document
	under the terms of the GNU Free Documentation License, Version 1.3 or
	any later version published by the Free Software Foundation; with the
	Invariant Sections being ``Free Software Needs Free Documentation''
	and ``GNU Lesser General Public License'', the Front-Cover texts being
	``A GNU Manual'', and with the Back-Cover Texts as in (a) below. A
	copy of the license is included in the section entitled "GNU Free
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	Previous: <a rel="previous" accesskey="p" href="Formatted-Input-Functions.html#Formatted-Input-Functions">Formatted Input Functions</a>,
	Up: <a rel="up" accesskey="u" href="Formatted-Input.html#Formatted-Input">Formatted Input</a>
	<hr>
	</div>

	<h4 class="subsection">12.14.9 Variable Arguments Input Functions</h4>

	<p>The functions <code>vscanf</code> and friends are provided so that you can
	define your own variadic <code>scanf</code>-like functions that make use of
	the same internals as the built-in formatted output functions.
	These functions are analogous to the <code>vprintf</code> series of output
	functions. See <a href="Variable-Arguments-Output.html#Variable-Arguments-Output">Variable Arguments Output</a>, for important
	information on how to use them.

	<p><strong>Portability Note:</strong> The functions listed in this section were
	introduced in ISO C99<!-- /@w --> and were before available as GNU extensions.

	<!-- stdio.h -->
	<!-- ISO -->
	<div class="defun">
	— Function: int <b>vscanf</b> (<var>const char *template, va_list ap</var>)<var><a name="index-vscanf-1089"></a></var><br>
	<blockquote><p>This function is similar to <code>scanf</code>, but instead of taking
	a variable number of arguments directly, it takes an argument list
	pointer <var>ap</var> of type <code>va_list</code> (see <a href="Variadic-Functions.html#Variadic-Functions">Variadic Functions</a>).
	</p></blockquote></div>

	<!-- wchar.h -->
	<!-- ISO -->
	<div class="defun">
	— Function: int <b>vwscanf</b> (<var>const wchar_t *template, va_list ap</var>)<var><a name="index-vwscanf-1090"></a></var><br>
	<blockquote><p>This function is similar to <code>wscanf</code>, but instead of taking
	a variable number of arguments directly, it takes an argument list
	pointer <var>ap</var> of type <code>va_list</code> (see <a href="Variadic-Functions.html#Variadic-Functions">Variadic Functions</a>).
	</p></blockquote></div>

	<!-- stdio.h -->
	<!-- ISO -->
	<div class="defun">
	— Function: int <b>vfscanf</b> (<var>FILE stream, const char template, va_list ap</var>)<var><a name="index-vfscanf-1091"></a></var><br>
	<blockquote><p>This is the equivalent of <code>fscanf</code> with the variable argument list
	specified directly as for <code>vscanf</code>.
	</p></blockquote></div>

	<!-- wchar.h -->
	<!-- ISO -->
	<div class="defun">
	— Function: int <b>vfwscanf</b> (<var>FILE stream, const wchar_t template, va_list ap</var>)<var><a name="index-vfwscanf-1092"></a></var><br>
	<blockquote><p>This is the equivalent of <code>fwscanf</code> with the variable argument list
	specified directly as for <code>vwscanf</code>.
	</p></blockquote></div>

	<!-- stdio.h -->
	<!-- ISO -->
	<div class="defun">
	— Function: int <b>vsscanf</b> (<var>const char s, const char template, va_list ap</var>)<var><a name="index-vsscanf-1093"></a></var><br>
	<blockquote><p>This is the equivalent of <code>sscanf</code> with the variable argument list
	specified directly as for <code>vscanf</code>.
	</p></blockquote></div>

	<!-- wchar.h -->
	<!-- ISO -->
	<div class="defun">
	— Function: int <b>vswscanf</b> (<var>const wchar_t s, const wchar_t template, va_list ap</var>)<var><a name="index-vswscanf-1094"></a></var><br>
	<blockquote><p>This is the equivalent of <code>swscanf</code> with the variable argument list
	specified directly as for <code>vwscanf</code>.
	</p></blockquote></div>

	<p>In GNU C, there is a special construct you can use to let the compiler
	know that a function uses a <code>scanf</code>-style format string. Then it
	can check the number and types of arguments in each call to the
	function, and warn you when they do not match the format string.
	For details, see <a href="../gcc/Function-Attributes.html#Function-Attributes">Declaring Attributes of Functions</a>.

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