/** @warning must be called before any I/O */
int ffio_set_buf_size(AVIOContext *s, int buf_size);
+/**
+ * Reallocate a given buffer for AVIOContext.
+ *
+ * @param s the AVIOContext to realloc.
+ * @param buf_size required new buffer size.
+ * @return 0 on success, a negative AVERROR on failure.
+ */
+int ffio_realloc_buf(AVIOContext *s, int buf_size);
+
/**
* Ensures that the requested seekback buffer size will be available
*