- * @param out_size size in bytes of the out buffer, it should be at
- * least 3/4 of the length of in
- * @return the number of bytes written, or a negative value in case of
- * error
+ * @param out buffer for decoded data
+ * @param in null-terminated input string
+ * @param out_size size in bytes of the out buffer, must be at
+ * least 3/4 of the length of in
+ * @return number of bytes written, or a negative value in case of
+ * invalid input