+/**
+ * Takes care of parsing the command-line arguments, loading the
+ * default configuration file (<<var_cf_def_file,`cf_def_file`>>) and processing
+ * configuration options. The calling convention is the same as with GNU getopt_long(),
+ * but you must prefix your own short/long options by the
+ * <<def_CF_LONG_OPTS,`CF_LONG_OPTS`>> or <<def_CF_SHORT_OPTS,`CF_SHORT_OPTS`>> or
+ * pass <<def_CF_NO_LONG_OPTS,`CF_NO_LONG_OPTS`>> if there are no long options.
+ *
+ * The default configuration file can be overwritten by the --config options,
+ * which must come first. During parsing of all other options, the configuration
+ * is already available.
+ **/