SSL_want(3) OpenSSL SSL_want(3) NNAAMMEE SSL_want, SSL_want_nothing, SSL_want_read, SSL_want_write, SSL_want_x509_lookup - obtain state information TLS/SSL I/O operation SSYYNNOOPPSSIISS #include int SSL_want(const SSL *ssl); int SSL_want_nothing(const SSL *ssl); int SSL_want_read(const SSL *ssl); int SSL_want_write(const SSL *ssl); int SSL_want_x509_lookup(const SSL *ssl); DDEESSCCRRIIPPTTIIOONN _S_S_L___w_a_n_t_(_) returns state information for the SSL object ssssll. The other SSL_want_*() calls are shortcuts for the possible states returned by _S_S_L___w_a_n_t_(_). NNOOTTEESS _S_S_L___w_a_n_t_(_) examines the internal state information of the SSL object. Its return values are similar to that of _S_S_L___g_e_t___e_r_r_o_r(3). Unlike _S_S_L___g_e_t___e_r_r_o_r(3), which also evaluates the error queue, the results are obtained by examining an internal state flag only. The information must therefore only be used for normal operation under non-blocking I/O. Error conditions are not handled and must be treated using _S_S_L___g_e_t___e_r_r_o_r(3). The result returned by _S_S_L___w_a_n_t_(_) should always be consistent with the result of _S_S_L___g_e_t___e_r_r_o_r(3). RREETTUURRNN VVAALLUUEESS The following return values can currently occur for _S_S_L___w_a_n_t_(_): SSL_NOTHING There is no data to be written or to be read. SSL_WRITING There are data in the SSL buffer that must be written to the under- lying BBIIOO layer in order to complete the actual SSL_*() operation. A call to _S_S_L___g_e_t___e_r_r_o_r(3) should return SSL_ERROR_WANT_WRITE. SSL_READING More data must be read from the underlying BBIIOO layer in order to complete the actual SSL_*() operation. A call to _S_S_L___g_e_t___e_r_r_o_r(3) should return SSL_ERROR_WANT_READ. SSL_X509_LOOKUP The operation did not complete because an application callback set by _S_S_L___C_T_X___s_e_t___c_l_i_e_n_t___c_e_r_t___c_b_(_) has asked to be called again. A call to _S_S_L___g_e_t___e_r_r_o_r(3) should return SSL_ERROR_WANT_X509_LOOKUP. _S_S_L___w_a_n_t___n_o_t_h_i_n_g_(_), _S_S_L___w_a_n_t___r_e_a_d_(_), _S_S_L___w_a_n_t___w_r_i_t_e_(_), _S_S_L___w_a_n_t___x_5_0_9___l_o_o_k_u_p_(_) return 1, when the corresponding condition is true or 0 otherwise. SSEEEE AALLSSOO _s_s_l(3), _e_r_r(3), _S_S_L___g_e_t___e_r_r_o_r(3) 1.0.1u 2016-09-22 SSL_want(3)