Else a later buffer resize in ffio_set_buf_size() will ABORT.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
* freed with av_free().
*
* @param buffer Memory block for input/output operations via AVIOContext.
+ * The buffer must be allocated with av_malloc() and friends.
* @param buffer_size The buffer size is very important for performance.
* For protocols with fixed blocksize it should be set to this blocksize.
* For others a typical size is a cache page, e.g. 4kb.