diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 53a003a95..7c87e672a 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,14 @@
+2012-03-03  Christopher Faylor  <me.cygwin2012@cgf.cx>
+
+	* fhandler_console.cc (fhandler_console::dup): Only set ctty when we
+	haven't specifically called setsid.
+	* fhandler_tty.cc (fhandler_pty_slave::dup): Ditto.  Also add comment
+	documenting research into rxvt problem.
+	* fhandler_termios.cc (fhandler_termios::tcsetpgrp): Don't check
+	specifically for myself->ctty == -1.  Test for > 0 as that is the
+	correct test.
+	(fhandler_termios::sigflush): Ditto.
+
 2012-03-02  Corinna Vinschen  <corinna@vinschen.de>
 
 	* flock.cc (allow_others_to_sync): Reorder conditional expression to
diff --git a/winsup/cygwin/fhandler_console.cc b/winsup/cygwin/fhandler_console.cc
index 4ed56635f..a30b717d2 100644
--- a/winsup/cygwin/fhandler_console.cc
+++ b/winsup/cygwin/fhandler_console.cc
@@ -759,7 +759,9 @@ fhandler_console::scroll_screen (int x1, int y1, int x2, int y2, int xn, int yn)
 int
 fhandler_console::dup (fhandler_base *child, int flags)
 {
-  myself->set_ctty (this, flags);
+  /* See comments in fhandler_pty_slave::dup */
+  if (myself->ctty != -2)
+    myself->set_ctty (this, flags);
   return 0;
 }
 
diff --git a/winsup/cygwin/fhandler_termios.cc b/winsup/cygwin/fhandler_termios.cc
index 36017dc63..70fb12877 100644
--- a/winsup/cygwin/fhandler_termios.cc
+++ b/winsup/cygwin/fhandler_termios.cc
@@ -99,7 +99,7 @@ fhandler_termios::tcsetpgrp (const pid_t pgid)
 int
 fhandler_termios::tcgetpgrp ()
 {
-  if (myself->ctty != -1 && myself->ctty == tc ()->ntty)
+  if (myself->ctty > 0 && myself->ctty == tc ()->ntty)
     return tc ()->pgid;
   set_errno (ENOTTY);
   return -1;
@@ -404,7 +404,7 @@ fhandler_termios::sigflush ()
 pid_t
 fhandler_termios::tcgetsid ()
 {
-  if (myself->ctty != -1 && myself->ctty == tc ()->ntty)
+  if (myself->ctty > 0 && myself->ctty == tc ()->ntty)
     return tc ()->getsid ();
   set_errno (ENOTTY);
   return -1;
diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
index b316a0aaf..547cf72b8 100644
--- a/winsup/cygwin/fhandler_tty.cc
+++ b/winsup/cygwin/fhandler_tty.cc
@@ -898,7 +898,16 @@ out:
 int
 fhandler_pty_slave::dup (fhandler_base *child, int flags)
 {
-  myself->set_ctty (this, flags);
+  /* This code was added in Oct 2001 for some undisclosed reason.
+     However, setting the controlling tty on a dup causes rxvt to
+     hang when the parent does a dup since the controlling pgid changes.
+     Specifically testing for -2 (ctty has been setsid'ed) works around
+     this problem.  However, it's difficult to see scenarios in which you
+     have a dup'able fd, no controlling tty, and not having run setsid.
+     So, we might want to consider getting rid of the set_ctty in tty-like dup
+     methods entirely at some point */
+  if (myself->ctty != -2)
+    myself->set_ctty (this, flags);
   report_tty_counts (child, "duped slave", "");
   return 0;
 }