diff --git a/sys/kern/tty_pty.c b/sys/kern/tty_pty.c
index eeb42931a80c..9c8300c40da3 100644
--- a/sys/kern/tty_pty.c
+++ b/sys/kern/tty_pty.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: tty_pty.c,v 1.91 2006/07/23 22:06:11 ad Exp $	*/
+/*	$NetBSD: tty_pty.c,v 1.92 2006/08/03 22:03:18 christos Exp $	*/
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1993
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: tty_pty.c,v 1.91 2006/07/23 22:06:11 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: tty_pty.c,v 1.92 2006/08/03 22:03:18 christos Exp $");
 
 #include "opt_compat_sunos.h"
 #include "opt_ptm.h"
@@ -753,6 +753,7 @@ again:
 				TTY_LOCK(tp);
 				/* check again for safety */
 				if (!ISSET(tp->t_state, TS_ISOPEN)) {
+					uip->
 					error = EIO;
 					goto out;
 				}
@@ -780,6 +781,8 @@ again:
 			TTY_LOCK(tp);
 			/* check again for safety */
 			if (!ISSET(tp->t_state, TS_ISOPEN)) {
+				/* adjust for data copied in but not written */
+				uio->uio_resid += cc;
 				error = EIO;
 				goto out;
 			}
@@ -812,6 +815,8 @@ block:
 	 * in outq, or space in rawq.
 	 */
 	if (!ISSET(tp->t_state, TS_CARR_ON)) {
+		/* adjust for data copied in but not written */
+		uio->uio_resid += cc;
 		error = EIO;
 		goto out;
 	}