diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 3e46685bb..c2a5ee3d8 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+2013-10-18  Christopher Faylor  <me.cygwin2013@cgf.cx>
+
+	* tty.cc (tty_list::allocate): Set sid to 0 rather than -1 since -1 is
+	an error condition.
+
 2013-10-16  Corinna Vinschen  <corinna@vinschen.de>
 
 	* fhandler_process.cc (format_process_ctty): Fix random content of
diff --git a/winsup/cygwin/tty.cc b/winsup/cygwin/tty.cc
index 7388ac1a3..01c53f933 100644
--- a/winsup/cygwin/tty.cc
+++ b/winsup/cygwin/tty.cc
@@ -141,7 +141,7 @@ tty_list::allocate (HANDLE& r, HANDLE& w)
       {
 	t = ttys + i;
 	t->init ();
-	t->setsid (-1);
+	t->setsid (0);
 	freetty = i;
 	break;
       }