X-Recipient:	archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status:	No, hits=-1.9 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RP_MATCHES_RCVD,T_TO_NO_BRKTS_FREEMAIL
X-Spam-Check-By:	sourceware.org
Message-ID:	<32593677.post@talk.nabble.com>
Date:	Tue, 4 Oct 2011 18:18:33 -0700 (PDT)
From:	"jan.kolar" <kolar AT math DOT cas DOT cz>
To:	cygwin AT cygwin DOT com
Subject:	Re: pressing ENTER scrambles scrolled MS-DOS-console
In-Reply-To:	<20111004123059.GB27229@calimero.vinschen.de>
MIME-Version:	1.0
References:	<000c01cc7c46$615cd310$24167930$@de> <20111004123059 DOT GB27229 AT calimero DOT vinschen DOT de>
X-IsSubscribed:	yes
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
List-Unsubscribe:	<mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com

Corinna Vinschen-2 wrote:
> 
> On Sep 26 14:18, Paul Maier wrote:
>> Hi,
>> 
>> scrolling up the console output to review the console history, then
>> pressing
>> Enter scrambles the console.
> 
> That's a long standing behaviour of the Cygwin console emulation.
> I guess it can be fixed, but somebody will have to do it.  In the
> meantime, try mintty as terminal.
> 
> 
> Corinna
> 
> -- 
> Corinna Vinschen                  Please, send mails regarding Cygwin to
> Cygwin Project Co-Leader          cygwin AT cygwin DOT com
> Red Hat
> 
> 

The problem is as below.
However it needs some thinking, checking and testing, since I have no idea
what that line was needed for.

diff --git i/fhandler_console.cc w/fhandler_console.cc
index 74b5cbd..f29426d 100644
--- i/fhandler_console.cc
+++ w/fhandler_console.cc
@@ -1089,7 +1127,27 @@ fhandler_console::cursor_set (bool rel_to_top, int x,
int y)

   dev_state->fillin_info (get_output_handle ());
   if (y > dev_state->info.winBottom)
-    y = dev_state->info.winBottom;
+    y = y;
+    // certainly not if doing CR:   y = dev_state->info.winBottom;
+    // (What purpose did that serve?)
+    // There is number of places that assume the following be noop with
respect to cursor's position:
+    //     cursor_get( &x, &y)
+    //     cursor_set( x,  y)
+    // For any of them the assignment that I removed is unacceptable.
+
+    // Test case 1:  while sleep 0.2; do echo -ne  "\r$x"; x=x$x; done
+    //               Now it works correctly when the user attempts to
scroll the window.
+    // Test case 2:  sleep 2  <enter>  {scroll up}
+    //               Now it does not scramble the console even if PS1
(effectively) starts with \n as usual.
+
+
+    // There is another problem, not fully manifested in this place:
+    // Nothing should depend on the window how it is currently scrolled by
the user.
+    // If there is any scrolling sub-window, it should be managed without
reference to winBottom/Top.
+    // If we have to place cursor, it should not depend on winBottom/Top.
+    // For example srTop / srBottom cannot be computed relative to
winBottom/Top.
+
   else if (y < 0)
     y = 0;
   else if (rel_to_top)

JK
-- 
View this message in context: http://old.nabble.com/pressing-ENTER-scrambles-scrolled-MS-DOS-console-tp32539946p32593677.html
Sent from the Cygwin list mailing list archive at Nabble.com.


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

- Raw text -