+/**
+ * Append path component to the existing path.
+ * Path separator '/' is placed between when needed.
+ * Resulting string have to be freed with av_free().
+ * @param path base path
+ * @param component component to be appended
+ * @return new path or NULL on error.
+ */
+char *av_append_path_component(const char *path, const char *component);
+