+ /** Stdin is always the root of a buffer tree. */
+ struct btr_node *btrn;
+ /** Use a buffer pool to minimize memcpy due to alignment problems. */
+ struct btr_pool *btrp;
+ /** The descriptor flags of STDIN at startup. */
+ int fd_flags;
+ /** Whether we have to set STDIN to nonblocking mode. */
+ bool must_set_nonblock_flag;