BIO_test_flags
int BIO_test_flags(const BIO *b, int flags);
#define BIO_get_flags(b) BIO_test_flags(b, ~(0x0))
BIO_test_flags(b, (BIO_FLAGS_RWS|BIO_FLAGS_SHOULD_RETRY))
#define BIO_should_read(a) BIO_test_flags(a, BIO_FLAGS_READ)
#define BIO_should_write(a) BIO_test_flags(a, BIO_FLAGS_WRITE)
#define BIO_should_io_special(a) BIO_test_flags(a, BIO_FLAGS_IO_SPECIAL)
#define BIO_retry_type(a) BIO_test_flags(a, BIO_FLAGS_RWS)
#define BIO_should_retry(a) BIO_test_flags(a, BIO_FLAGS_SHOULD_RETRY)
LCRYPTO_ALIAS(BIO_test_flags);
LCRYPTO_USED(BIO_test_flags);