BIO_TYPE_SOURCE_SINK
BIO_TYPE_SOURCE_SINK,
#define BIO_TYPE_MEM (1 | BIO_TYPE_SOURCE_SINK)
#define BIO_TYPE_FILE (2 | BIO_TYPE_SOURCE_SINK)
#define BIO_TYPE_FD (4 | BIO_TYPE_SOURCE_SINK | BIO_TYPE_DESCRIPTOR)
#define BIO_TYPE_SOCKET (5 | BIO_TYPE_SOURCE_SINK | BIO_TYPE_DESCRIPTOR)
#define BIO_TYPE_NULL (6 | BIO_TYPE_SOURCE_SINK)
#define BIO_TYPE_CONNECT (12 | BIO_TYPE_SOURCE_SINK | BIO_TYPE_DESCRIPTOR)
#define BIO_TYPE_ACCEPT (13 | BIO_TYPE_SOURCE_SINK | BIO_TYPE_DESCRIPTOR)
#define BIO_TYPE_BIO (19 | BIO_TYPE_SOURCE_SINK) /* half a BIO pair */
#define BIO_TYPE_DGRAM (21 | BIO_TYPE_SOURCE_SINK | BIO_TYPE_DESCRIPTOR)
#define BIO_TYPE_DGRAM_SCTP (24 | BIO_TYPE_SOURCE_SINK | BIO_TYPE_DESCRIPTOR)
#define BIO_TYPE_CORE_TO_PROV (25 | BIO_TYPE_SOURCE_SINK)
#define BIO_TYPE_DGRAM_PAIR (26 | BIO_TYPE_SOURCE_SINK)
#define BIO_TYPE_DGRAM_MEM (27 | BIO_TYPE_SOURCE_SINK)