+/** @brief print to allocated string (reimplemented when not provided by the system)
+ *
+ * The functions asprintf() and vasprintf() are analogues of
+ * sprintf() and vsprintf(), except that they allocate a string large
+ * enough to hold the output including the terminating null byte, and
+ * return a pointer to it via the first parameter. This pointer
+ * should be passed to free(3) to release the allocated storage when
+ * it is no longer needed.
+ */