Type Definition openssl_sys::SSL_client_hello_cb_fn
pub type SSL_client_hello_cb_fn = Option<unsafe extern "C" fn(*mut SSL, *mut c_int, *mut c_void) -> c_int>;The portability is definied by:
#[cfg(ossl111)]pub type SSL_client_hello_cb_fn = Option<unsafe extern "C" fn(*mut SSL, *mut c_int, *mut c_void) -> c_int>;#[cfg(ossl111)]