/* Options on tls_close */
-#define TLS_NO_SHUTDOWN 0
-#define TLS_SHUTDOWN_NOWAIT 1
-#define TLS_SHUTDOWN_WAIT 2
+#define TLS_NO_SHUTDOWN 0 /* Just forget the context */
+#define TLS_SHUTDOWN_NOWAIT 1 /* Send alert; do not wait */
+#define TLS_SHUTDOWN_WAIT 2 /* Send alert & wait for peer's alert */
+#define TLS_SHUTDOWN_WONLY 3 /* only wait for peer's alert */
#ifdef COMPILE_UTILITY