Type Definition openssl_sys::SSL_CTX_keylog_cb_func
pub type SSL_CTX_keylog_cb_func = Option<unsafe extern "C" fn(*const SSL, *const c_char)>;
The portability is definied by:
#[cfg(ossl111)]
pub type SSL_CTX_keylog_cb_func = Option<unsafe extern "C" fn(*const SSL, *const c_char)>;
#[cfg(ossl111)]