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1.1 misho 3: So far, we have only parsed configuration data from files.
4: libConfuse can also parse buffers, or in-memory character
5: strings. We will use this to fix a problem in the previous code.
6: </p><p>
7: The problem is that without a configuration file, the hello program
8: will not print anything. We want it to at least print the standard
9: greeting "Hello, World!" if no configuration file is available.
10: </p><p>
11: We can't have a default value for a section that can be specified
12: multiple times (ie, a section with the CFGF_MULTI flag set).
13: Instead we will parse a default configuration string if no section
14: has been parsed:
15: </p><a id="listing6"></a><pre class="programlisting">
16: 1 #include <stdio.h>
17: 2 #include <confuse.h>
18: 3
19: 4 int main(void)
20: 5 {
21: 6 /* ... setup options ... */
22: 7
23: 8 cfg = cfg_init(opts, CFGF_NONE);
24: 9 cfg_parse(cfg, "hello.conf");
25: 10
26: 11 if(cfg_size(cfg, "greeting") == 0)
27: 12 {
28: 13 cfg_parse_buf(cfg, "greeting Hello {}");
29: 14 }
30: 15
31: 16 /* ... print the greetings ... */
32: 17 }
33: </pre><p>
34: Only the changes from the previous code is shown here. We check if
35: the size of the "greeting" section is zero (ie, no section has been
36: defined). In that case we call <code class="function">cfg_parse_buf()</code>
37: to parse a default in-memory string "greeting Hello {}". This
38: string defines a greeting section with title Hello, but without any
39: sub-options. This way we rely on the default values of the
40: (sub-)options "targets" and "repeat".
41: </p><p>
42: When this program is run, it issues the well-known standard greeting
43: "Hello, World!" if no configuration file is present.
1.1.1.2 ! misho 44: </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ar01s04.html">Prev</a> </td><td width="20%" align="center"> </td><td width="40%" align="right"> <a accesskey="n" href="ar01s06.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">4. Using sections </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 6. Validating callback functions</td></tr></table></div></body></html>
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