Improved in-source documentation (interfaces are divided into modules).

src/conf.c

@@ -1164,7 +1164,8 @@ int snd_config_search_alias(snd_config_t *config,
 /** File resident in home directory used for user specific ALSA configuration */
 #define USR_ASOUNDRC ".asoundrc"
 
-/** Config top node */
+/** \ingroup Config
+  * Config top node */
 snd_config_t *snd_config = NULL;
 
 /** 

src/error.c

@@ -80,6 +80,7 @@ static void snd_lib_error_default(const char *file, int line, const char *functi
 }
 
 /**
+ * \ingroup Error
  * Pointer to the error handler function.
  */
 snd_lib_error_handler_t *snd_lib_error = snd_lib_error_default;