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1: <?xml version="1.0" encoding="ANSI_X3.4-1968" standalone="no"?> 2: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3: <html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968" /><title>8. Functions</title><link rel="stylesheet" href="tutorial.css" type="text/css" /><meta name="generator" content="DocBook XSL Stylesheets V1.75.2" /><link rel="home" href="index.html" title="libConfuse tutorial" /><link rel="up" href="index.html" title="libConfuse tutorial" /><link rel="prev" href="ar01s07.html" title="7. Value parsing callback" /><link rel="next" href="ar01s09.html" title="9. Saving configuration files" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">8. Functions</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s07.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s09.html">Next</a></td></tr></table><hr /></div><div class="sect1" title="8. Functions"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="id442474"></a>8. Functions</h2></div></div></div><p> 4: libConfuse supports functions to parse options that does not fit 5: well in the general syntax. Functions can be called with a variable 6: number of arguments. No data from the function or any arguments are 7: stored by libConfuse after the function has run. It is up to the caller 8: to process and/or save the data. 9: </p><p> 10: A function is defined with a <code class="function">CFG_FUNC</code> macro. 11: It takes two arguments: the name of the function and a function 12: callback. The callback is defined as: 13: </p><pre class="programlisting"> 14: typedef int (*cfg_func_t)(cfg_t *cfg, cfg_opt_t *opt, 15: int argc, const char **argv); 16: </pre><p> 17: </p><div class="sect2" title="8.1. Predefined functions"><div class="titlepage"><div><div><h3 class="title"><a id="id442506"></a>8.1. Predefined functions</h3></div></div></div><p> 18: Currently there is only one pre-defined function: 19: <code class="function">cfg_include()</code>. This function includes 20: another configuration file. Configuration data is immediately 21: read from the included file, and is returned to the position 22: right after the include() statement upon end of file. 23: </p><p> 24: To use this function, include a <code class="function">CFG_FUNC()</code> 25: entry in your options: 26: </p><pre class="programlisting"> 27: cfg_opt_t opts[] = { 28: CFG_FUNC("include", cfg_include), 29: CFG_END() 30: }; 31: </pre><p> 32: In the configuration file, it is used in the following way: 33: </p><pre class="programlisting"> 34: include("included.conf") 35: </pre></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ar01s07.html">Prev</a> </td><td width="20%" align="center"> </td><td width="40%" align="right"> <a accesskey="n" href="ar01s09.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">7. Value parsing callback </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 9. Saving configuration files</td></tr></table></div></body></html>