1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>vscnprintf</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The Linux Kernel API"><link rel="up" href="libc.html#idp1122555668" title="String Conversions"><link rel="prev" href="API-vsnprintf.html" title="vsnprintf"><link rel="next" href="API-snprintf.html" title="snprintf"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">vscnprintf</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-vsnprintf.html">Prev</a>&#160;</td><th width="60%" align="center">String Conversions</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-snprintf.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-vscnprintf"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>vscnprintf &#8212; 
2     Format a string and place it in a buffer
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">vscnprintf </b>(</code></td><td>char * <var class="pdparam">buf</var>, </td></tr><tr><td>&#160;</td><td>size_t <var class="pdparam">size</var>, </td></tr><tr><td>&#160;</td><td>const char * <var class="pdparam">fmt</var>, </td></tr><tr><td>&#160;</td><td>va_list <var class="pdparam">args</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1122619204"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>buf</code></em></span></dt><dd><p>
4     The buffer to place the result into
5    </p></dd><dt><span class="term"><em class="parameter"><code>size</code></em></span></dt><dd><p>
6     The size of the buffer, including the trailing null space
7    </p></dd><dt><span class="term"><em class="parameter"><code>fmt</code></em></span></dt><dd><p>
8     The format string to use
9    </p></dd><dt><span class="term"><em class="parameter"><code>args</code></em></span></dt><dd><p>
10     Arguments for the format string
11    </p></dd></dl></div></div><div class="refsect1"><a name="idp1122623812"></a><h2>Description</h2><p>
12   The return value is the number of characters which have been written into
13   the <em class="parameter"><code>buf</code></em> not including the trailing '\0'. If <em class="parameter"><code>size</code></em> is == 0 the function
14   returns 0.
15   </p><p>
16
17   If you're not already dealing with a va_list consider using <code class="function">scnprintf</code>.
18   </p><p>
19
20   See the <code class="function">vsnprintf</code> documentation for format string extensions over C99.
21</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-vsnprintf.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="libc.html#idp1122555668">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-snprintf.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">vsnprintf</span>&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;<span class="phrase">snprintf</span></td></tr></table></div></body></html>
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