SSL_want
LSSL_USED(SSL_want);
int SSL_want(const SSL *s);
#define SSL_want_nothing(s) (SSL_want(s) == SSL_NOTHING)
#define SSL_want_read(s) (SSL_want(s) == SSL_READING)
#define SSL_want_write(s) (SSL_want(s) == SSL_WRITING)
#define SSL_want_x509_lookup(s) (SSL_want(s) == SSL_X509_LOOKUP)
LSSL_ALIAS(SSL_want);