-long ssl2_callback_ctrl(SSL *s,int cmd, void (*fp)());
-long ssl2_ctx_callback_ctrl(SSL_CTX *s,int cmd, void (*fp)());
-int ssl2_pending(SSL *s);
+long ssl2_callback_ctrl(SSL *s,int cmd, void (*fp)(void));
+long ssl2_ctx_callback_ctrl(SSL_CTX *s,int cmd, void (*fp)(void));
+int ssl2_pending(const SSL *s);