SSL_DO_HANDSHAKE(3ssl) OpenSSL SSL_DO_HANDSHAKE(3ssl) SSL_do_handshake - TLS/SSL #include int SSL_do_handshake(SSL *ssl); SSL_do_handshake() SSL/TLS. . SSL_set_connect_state(3) SSL_set_accept_state(3). SSL_do_handshake() BIO . BIO blocking SSL_do_handshake() . BIO nonblocking SSL_do_handshake() BIO SSL_do_handshake() . SSL_get_error() SSL_do_handshake() SSL_ERROR_WANT_READ SSL_ERROR_WANT_WRITE. SSL_do_handshake(). BIO . select() . BIO BIO BIO . : 0 TLS/SSL TLS/SSL. SSL_get_error() ret . 1 TLS/SSL TLS/SSL. <0 TLS/SSL . . BIOs . SSL_get_error() ret . SSL_get_error(3), SSL_connect(3), SSL_accept(3), ssl(7), bio(7), SSL_set_connect_state(3) 2002-2020 OpenSSL. . Apache 2.0 ( ""). . LICENSE . 3 . . : . 3.6.2 7 2026 SSL_DO_HANDSHAKE(3ssl)