+ * Split a line into words which are separated by whitespace.
+ *
+ * In contrast to gengetopt's string parser, double quotes, backslash-escaped
+ * characters and special characters like \p \\n are honored. The result
+ * contains pointers to copies of the words contained in \a line and has to be
+ * freed by using \ref free_argv().
+ *
+ * \param line The line to be split.
+ * \param result The array of words is returned here.
+ *