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4            Of course, not only strings can be specified in the configuration file.
5            libConfuse can parse strings, integers, booleans and floating point values.
6            These are the fundamental values, and they are all also available as lists.
7            We'll talk more about lists in the next chapter.
8        </p><p>
9            The macros used to initialize a string, integer, boolean and a
10            float is, respectively, <code class="function">CFG_STR()</code>,
11            <code class="function">CFG_INT()</code>, <code class="function">CFG_BOOL()</code>,
12            <code class="function">CFG_FLOAT()</code> and
13            <code class="function">CFG_PTR()</code>. All macros take three parameters:
14            the name of the option, a default value and flags. To retrieve the
15            values, use <code class="function">cfg_getstr()</code>,
16            <code class="function">cfg_getint()</code>,
17            <code class="function">cfg_getbool()</code>,
18            <code class="function">cfg_getfloat()</code> or
19            <code class="function">cfg_getptr()</code>, respectively.
20        </p><p>
21            Let's introduce an integer option that tells us how many times to print the
22            greeting:
23        </p><a id="listing3"></a><pre class="programlisting">
241	#include &lt;stdio.h&gt;
252	#include &lt;confuse.h&gt;
263	
274	int main(void)
285	{
296	    cfg_opt_t opts[] =
307	    {
318	        CFG_STR("target", "World", CFGF_NONE),
329	        CFG_INT("repeat", 1, CFGF_NONE),
3310	        CFG_END()
3411	    };
3512	    cfg_t *cfg;
3613	    int repeat;
3714	
3815	    cfg = cfg_init(opts, CFGF_NONE);
3916	    if(cfg_parse(cfg, "hello.conf") == CFG_PARSE_ERROR)
4017	        return 1;
4118	
4219	    repeat = cfg_getint(cfg, "repeat");
4320	    while(repeat--)
4421	        printf("Hello, %s!\n", cfg_getstr(cfg, "target"));
4522	
4623	    cfg_free(cfg);
4724	    return 0;
4825	}
4926	
50</pre><p>
51            Here we have used the <code class="function">CFG_INT()</code> macro to
52            initialize an integer option named "repeat". The default value is 1
53            as in the standard greeting. The value is retrieved with
54            <code class="function">cfg_getint()</code>.
55        </p><p><a id="negative-repeat-problem"></a>
56            But, wait a moment, what if the user specified a negative value for
57            "repeat"?  Or a too large positive value? libConfuse can handle
58            that with a so-called validating callback. We'll come back to this
59            problem later on, but we will first take a look at lists.
60        </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="index.html">Prev</a>&#160;</td><td width="20%" align="center">&#160;</td><td width="40%" align="right">&#160;<a accesskey="n" href="ar01s03.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">libConfuse tutorial&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;3.&#160;Introducing lists</td></tr></table></div></body></html>
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