bug#1494: emacs -nw inserts unwanted chars if user is impatient

bug#1494: emacs -nw inserts unwanted chars if user is impatient

[Paul R]

Hi,

I usually work on X version of emacs 23. However, sometime, I just want
to alter a config file from the terminal. In this case I type 

   emacs -nw conf_file.conf

Very often I know that the line I want to go to is fairly low so before
emacs has finished to load I'm already pressing C-n waiting for the
display to show line and point. I guess a lot of user do the same and
often don't wait for the display to finish before typing what they want.

In this particular case, emacs would insert strange chars at point, for
example : 1;1704;0c

You won't be warned, and it will be saved along with your real
modifications, which is embarassing.

To reproduce, open any multiline file from the terminal, for example
.bash_history, with 'emacs -nw' and immediatly maintain C-n until the
display come up entirely. You should find at point the strange chars.

Tested with emacs23cvs with -Q on Gnu/Linux with xterm and
gnome-terminal.


-- 
  Paul

bug#1494: marked as done (emacs -nw inserts unwanted chars if user is impatient)

[Emacs bug Tracking System]

[-- Attachment #1: Type: text/plain, Size: 868 bytes --]


Your message dated Fri, 05 Dec 2008 22:57:12 -0500
with message-id <87ljuuot0n.fsf@cyd.mit.edu>
and subject line Re: emacs -nw inserts unwanted chars if user is impatient
has caused the Emacs bug report #1494,
regarding emacs -nw inserts unwanted chars if user is impatient
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

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-- 
1494: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=1494
Emacs Bug Tracking System
Contact don@donarmstrong.com with problems

[-- Attachment #2: Type: message/rfc822, Size: 3179 bytes --]

From: Paul R <paul.r.ml@gmail.com>
To: submit@emacsbugs.donarmstrong.com
Subject: emacs -nw inserts unwanted chars if user is impatient
Date: Thu, 04 Dec 2008 22:39:28 +0100
Message-ID: <87d4g78vsf.fsf@gmail.com>

Hi,

I usually work on X version of emacs 23. However, sometime, I just want
to alter a config file from the terminal. In this case I type 

   emacs -nw conf_file.conf

Very often I know that the line I want to go to is fairly low so before
emacs has finished to load I'm already pressing C-n waiting for the
display to show line and point. I guess a lot of user do the same and
often don't wait for the display to finish before typing what they want.

In this particular case, emacs would insert strange chars at point, for
example : 1;1704;0c

You won't be warned, and it will be saved along with your real
modifications, which is embarassing.

To reproduce, open any multiline file from the terminal, for example
.bash_history, with 'emacs -nw' and immediatly maintain C-n until the
display come up entirely. You should find at point the strange chars.

Tested with emacs23cvs with -Q on Gnu/Linux with xterm and
gnome-terminal.


-- 
  Paul



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From: Chong Yidong <cyd@stupidchicken.com>
To: 1494-done@emacsbugs.donarmstrong.com
Subject: Re: emacs -nw inserts unwanted chars if user is impatient
Date: Fri, 05 Dec 2008 22:57:12 -0500
Message-ID: <87ljuuot0n.fsf@cyd.mit.edu>

I don't see any other way to handle this, so I've checked in the fix
involving discarding pending input before reading the reply to the
terminal attributes query.

bug#1495: emacs -nw inserts unwanted chars if user is impatient

[Paul R]

Hi,

I usually work on X version of emacs 23. However, sometime, I just want
to alter a config file from the terminal. In this case I type 

   emacs -nw conf_file.conf

Very often I know that the line I want to go to is fairly low so before
emacs has finished to load I'm already pressing C-n waiting for the
display to show line and point. I guess a lot of user do the same and
often don't wait for the display to finish before typing what they want.

In this particular case, emacs would insert strange chars at point, for
example : 1;1704;0c

You won't be warned, and it will be saved along with your real
modifications, which is embarassing.

To reproduce, open any multiline file from the terminal, for example
.bash_history, with 'emacs -nw' and immediatly maintain C-n until the
display come up entirely. You should find at point the strange chars.

Tested with emacs23cvs with -Q on Gnu/Linux with xterm and
gnome-terminal.


-- 
  Paul

bug#1495: marked as done (emacs -nw inserts unwanted chars if user is impatient)

[Emacs bug Tracking System]

[-- Attachment #1: Type: text/plain, Size: 868 bytes --]


Your message dated Fri, 05 Dec 2008 22:57:12 -0500
with message-id <87ljuuot0n.fsf@cyd.mit.edu>
and subject line Re: emacs -nw inserts unwanted chars if user is impatient
has caused the Emacs bug report #1494,
regarding emacs -nw inserts unwanted chars if user is impatient
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact don@donarmstrong.com
immediately.)


-- 
1494: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=1494
Emacs Bug Tracking System
Contact don@donarmstrong.com with problems

[-- Attachment #2: Type: message/rfc822, Size: 3240 bytes --]

From: Paul R <paul.r.ml@gmail.com>
To: submit@emacsbugs.donarmstrong.com
Subject: emacs -nw inserts unwanted chars if user is impatient
Date: Thu, 04 Dec 2008 22:46:20 +0100
Message-ID: <87bpvr8vgz.fsf@gmail.com>


Hi,

I usually work on X version of emacs 23. However, sometime, I just want
to alter a config file from the terminal. In this case I type 

   emacs -nw conf_file.conf

Very often I know that the line I want to go to is fairly low so before
emacs has finished to load I'm already pressing C-n waiting for the
display to show line and point. I guess a lot of user do the same and
often don't wait for the display to finish before typing what they want.

In this particular case, emacs would insert strange chars at point, for
example : 1;1704;0c

You won't be warned, and it will be saved along with your real
modifications, which is embarassing.

To reproduce, open any multiline file from the terminal, for example
.bash_history, with 'emacs -nw' and immediatly maintain C-n until the
display come up entirely. You should find at point the strange chars.

Tested with emacs23cvs with -Q on Gnu/Linux with xterm and
gnome-terminal.


-- 
  Paul



[-- Attachment #3: Type: message/rfc822, Size: 1083 bytes --]

From: Chong Yidong <cyd@stupidchicken.com>
To: 1494-done@emacsbugs.donarmstrong.com
Subject: Re: emacs -nw inserts unwanted chars if user is impatient
Date: Fri, 05 Dec 2008 22:57:12 -0500
Message-ID: <87ljuuot0n.fsf@cyd.mit.edu>

I don't see any other way to handle this, so I've checked in the fix
involving discarding pending input before reading the reply to the
terminal attributes query.

bug#1495: emacs -nw inserts unwanted chars if user is impatient

[Chong Yidong]

Dan Nicolaescu <dann@ics.uci.edu> writes:

> I'm fairly confident this is due to the code in xterm.el that deals
> with modifyOtherKeys, the input probably comes while emacs is waiting
> from an answer from xterm.

This indeed seems to be the problem.

Discard pending input before doing the terminal query seems to fix the
bug for me.  I don't know if it's possible for the user's input to come
inat exactly at the correct moment to fool the terminal query; if so, a
more complicated solution might be required.

Thoughts?

*** trunk/lisp/term/xterm.el.~1.59.~	2008-09-30 20:01:30.000000000 -0400
--- trunk/lisp/term/xterm.el	2008-12-04 23:07:47.000000000 -0500
***************
*** 475,480 ****
--- 475,481 ----
  	  (str nil))
        ;; Try to find out the type of terminal by sending a "Secondary
        ;; Device Attributes (DA)" query.
+       (discard-input)
        (send-string-to-terminal "\e[>0c")
  
        ;; The reply should be of the form: \e [ > NUMBER1 ; NUMBER2 ; NUMBER3 c

bug#1495: emacs -nw inserts unwanted chars if user is impatient

[Stefan Monnier]

> Discard pending input before doing the terminal query seems to fix the
> bug for me.  I don't know if it's possible for the user's input to come
> inat exactly at the correct moment to fool the terminal query; if so, a
> more complicated solution might be required.

While arguing that there's probably no way to do much better than that,
it occurred to me that "the right way" to do it might be to move the
"check for \e [ > NUMBER1 ; NUMBER2 ; NUMBER3 c and run
xterm-turn-on-modify-other-keys if applicable" into the
input-decode-map.


        Stefan