bug#2138: 23.0.60; --daemon and ediff-window-setup-function

bug#2138: 23.0.60; --daemon and ediff-window-setup-function

[Stephen Berman]

Start Emacs like this:

1. emacs -Q --eval "(require 'ediff)"
2. emacsclient -c
3. C-h v ediff-window-setup-function
=> ediff-setup-windows-multiframe

Now start Emacs like this:

1. emacs -Q --daemon --eval "(require 'ediff)"
2. emacsclient -c
3. C-h v ediff-window-setup-function
=> ediff-setup-windows-plain


I haven't tried debugging this, but my first guess is that
ediff-setup-windows-multiframe requires non-nil window-system but (still
guessing) when there is no frame window-system evaluates to nil.


In GNU Emacs 23.0.60.31 (i686-pc-linux-gnu, GTK+ Version 2.14.4)
 of 2009-01-31 on escher
Windowing system distributor `The X.Org Foundation', version 11.0.10502000
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: @im=local
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

bug#2138: 23.0.60; --daemon and ediff-window-setup-function

[Dan Nicolaescu]

Stephen Berman <stephen.berman@gmx.net> writes:

  > Start Emacs like this:
  > 
  > 1. emacs -Q --eval "(require 'ediff)"
  > 2. emacsclient -c
  > 3. C-h v ediff-window-setup-function
  > => ediff-setup-windows-multiframe
  > 
  > Now start Emacs like this:
  > 
  > 1. emacs -Q --daemon --eval "(require 'ediff)"
  > 2. emacsclient -c
  > 3. C-h v ediff-window-setup-function
  > => ediff-setup-windows-plain
  > 
  > 
  > I haven't tried debugging this, but my first guess is that
  > ediff-setup-windows-multiframe requires non-nil window-system but (still
  > guessing) when there is no frame window-system evaluates to nil.

You can take --daemon out of this equation, you'd  get the same when
doing 
emacs -Q and emacs -Q -nw

bug#2138: 23.0.60; --daemon and ediff-window-setup-function

[Stephen Berman]

On Sat, 31 Jan 2009 22:05:07 -0800 (PST) Dan Nicolaescu <dann@ics.uci.edu> wrote:

> Stephen Berman <stephen.berman@gmx.net> writes:
>
>   > Start Emacs like this:
>   > 
>   > 1. emacs -Q --eval "(require 'ediff)"
>   > 2. emacsclient -c
>   > 3. C-h v ediff-window-setup-function
>   > => ediff-setup-windows-multiframe
>   > 
>   > Now start Emacs like this:
>   > 
>   > 1. emacs -Q --daemon --eval "(require 'ediff)"
>   > 2. emacsclient -c
>   > 3. C-h v ediff-window-setup-function
>   > => ediff-setup-windows-plain
>   > 
>   > 
>   > I haven't tried debugging this, but my first guess is that
>   > ediff-setup-windows-multiframe requires non-nil window-system but (still
>   > guessing) when there is no frame window-system evaluates to nil.
>
> You can take --daemon out of this equation, you'd  get the same when
> doing 
> emacs -Q and emacs -Q -nw

I should have been more explicit about the point of this bug report,
which is this: when I invoke `emacsclient -c' under X11, I expect the
usual behavior under X11, but in the above case, --daemon apparently
circumvents this behavior.

I cannot tell from the current documentation when using --daemon has
this effect and when it doesn't.  Hence I cannot tell whether this is a
bug or a limitation of the current implementation.  So I hope this and
similar bug reports lead to both more complete documentation and either
a bug fix or, at some point, a more feature-rich implementation.

Steve Berman

bug#2138: 23.0.60; --daemon and ediff-window-setup-function

[Dan Nicolaescu]

Stephen Berman <stephen.berman@gmx.net> writes:

  > On Sat, 31 Jan 2009 22:05:07 -0800 (PST) Dan Nicolaescu <dann@ics.uci.edu> wrote:
  > 
  > > Stephen Berman <stephen.berman@gmx.net> writes:
  > >
  > >   > Start Emacs like this:
  > >   > 
  > >   > 1. emacs -Q --eval "(require 'ediff)"
  > >   > 2. emacsclient -c
  > >   > 3. C-h v ediff-window-setup-function
  > >   > => ediff-setup-windows-multiframe
  > >   > 
  > >   > Now start Emacs like this:
  > >   > 
  > >   > 1. emacs -Q --daemon --eval "(require 'ediff)"
  > >   > 2. emacsclient -c
  > >   > 3. C-h v ediff-window-setup-function
  > >   > => ediff-setup-windows-plain
  > >   > 
  > >   > 
  > >   > I haven't tried debugging this, but my first guess is that
  > >   > ediff-setup-windows-multiframe requires non-nil window-system but (still
  > >   > guessing) when there is no frame window-system evaluates to nil.
  > >
  > > You can take --daemon out of this equation, you'd  get the same when
  > > doing 
  > > emacs -Q and emacs -Q -nw
  > 
  > I should have been more explicit about the point of this bug report,
  > which is this: when I invoke `emacsclient -c' under X11, I expect the
  > usual behavior under X11, but in the above case, --daemon apparently
  > circumvents this behavior.

Again, you get the same problem if you do:
emacs -Q -nw -f server-start  --eval "(require 'ediff)"
emacsclient -c 
M-x ediff

and you have a problem if you do
emacs -Q -f server-start  --eval "(require 'ediff)"
emacsclient -t
M-x ediff

  > I cannot tell from the current documentation when using --daemon has
  > this effect and when it doesn't.  Hence I cannot tell whether this is a
  > bug or a limitation of the current implementation.  So I hope this and
  > similar bug reports lead to both more complete documentation and either
  > a bug fix or, at some point, a more feature-rich implementation.

Not really, this is not a problem with --daemon, it's a problem in the
ediff implementation that it evaluates ediff-window-setup-function at
load time.  This is not appropriate anymore now when you can have both
X11 and tty frames in the same emacs session.

bug#2138: 23.0.60; --daemon and ediff-window-setup-function

[Stephen Berman]

On Sun, 1 Feb 2009 06:50:11 -0800 (PST) Dan Nicolaescu <dann@ics.uci.edu> wrote:

> Stephen Berman <stephen.berman@gmx.net> writes:
>
>   > On Sat, 31 Jan 2009 22:05:07 -0800 (PST) Dan Nicolaescu <dann@ics.uci.edu> wrote:
>   > 
>   > > Stephen Berman <stephen.berman@gmx.net> writes:
>   > >
>   > >   > Start Emacs like this:
>   > >   > 
>   > >   > 1. emacs -Q --eval "(require 'ediff)"
>   > >   > 2. emacsclient -c
>   > >   > 3. C-h v ediff-window-setup-function
>   > >   > => ediff-setup-windows-multiframe
>   > >   > 
>   > >   > Now start Emacs like this:
>   > >   > 
>   > >   > 1. emacs -Q --daemon --eval "(require 'ediff)"
>   > >   > 2. emacsclient -c
>   > >   > 3. C-h v ediff-window-setup-function
>   > >   > => ediff-setup-windows-plain
>   > >   > 
>   > >   > 
>   > >   > I haven't tried debugging this, but my first guess is that
>   > >   > ediff-setup-windows-multiframe requires non-nil window-system but (still
>   > >   > guessing) when there is no frame window-system evaluates to nil.
>   > >
>   > > You can take --daemon out of this equation, you'd  get the same when
>   > > doing 
>   > > emacs -Q and emacs -Q -nw
>   > 
>   > I should have been more explicit about the point of this bug report,
>   > which is this: when I invoke `emacsclient -c' under X11, I expect the
>   > usual behavior under X11, but in the above case, --daemon apparently
>   > circumvents this behavior.
>
> Again, you get the same problem if you do:
> emacs -Q -nw -f server-start  --eval "(require 'ediff)"
> emacsclient -c 
> M-x ediff
>
> and you have a problem if you do
> emacs -Q -f server-start  --eval "(require 'ediff)"
> emacsclient -t
> M-x ediff

Ok, now I see what you meant.

>   > I cannot tell from the current documentation when using --daemon has
>   > this effect and when it doesn't.  Hence I cannot tell whether this is a
>   > bug or a limitation of the current implementation.  So I hope this and
>   > similar bug reports lead to both more complete documentation and either
>   > a bug fix or, at some point, a more feature-rich implementation.
>
> Not really, this is not a problem with --daemon, it's a problem in the
> ediff implementation that it evaluates ediff-window-setup-function at
> load time.  This is not appropriate anymore now when you can have both
> X11 and tty frames in the same emacs session.

Yes, I too now see this is an ediff bug.  Thanks for the response!

Steve Berman

bug#2138: 23.0.60; --daemon and ediff-window-setup-function

[Eli Zaretskii]

> Date: Sun, 1 Feb 2009 06:50:11 -0800 (PST)
> From: Dan Nicolaescu <dann@ics.uci.edu>
> Cc: 2138@emacsbugs.donarmstrong.com
> 
> Stephen Berman <stephen.berman@gmx.net> writes:
> 
>   > On Sat, 31 Jan 2009 22:05:07 -0800 (PST) Dan Nicolaescu <dann@ics.uci.edu> wrote:
>   > 
>   > > Stephen Berman <stephen.berman@gmx.net> writes:
>   > >
>   > >   > Start Emacs like this:
>   > >   > 
>   > >   > 1. emacs -Q --eval "(require 'ediff)"
>   > >   > 2. emacsclient -c
>   > >   > 3. C-h v ediff-window-setup-function
>   > >   > => ediff-setup-windows-multiframe
>   > >   > 
>   > >   > Now start Emacs like this:
>   > >   > 
>   > >   > 1. emacs -Q --daemon --eval "(require 'ediff)"
>   > >   > 2. emacsclient -c
>   > >   > 3. C-h v ediff-window-setup-function
>   > >   > => ediff-setup-windows-plain
>   > >   > 
>   > >   > 
>   > >   > I haven't tried debugging this, but my first guess is that
>   > >   > ediff-setup-windows-multiframe requires non-nil window-system but (still
>   > >   > guessing) when there is no frame window-system evaluates to nil.
>   > >
>   > > You can take --daemon out of this equation, you'd  get the same when
>   > > doing 
>   > > emacs -Q and emacs -Q -nw
>   > 
>   > I should have been more explicit about the point of this bug report,
>   > which is this: when I invoke `emacsclient -c' under X11, I expect the
>   > usual behavior under X11, but in the above case, --daemon apparently
>   > circumvents this behavior.
> 
> Again, you get the same problem if you do:
> emacs -Q -nw -f server-start  --eval "(require 'ediff)"
> emacsclient -c 
> M-x ediff
> 
> and you have a problem if you do
> emacs -Q -f server-start  --eval "(require 'ediff)"
> emacsclient -t
> M-x ediff
> 
>   > I cannot tell from the current documentation when using --daemon has
>   > this effect and when it doesn't.  Hence I cannot tell whether this is a
>   > bug or a limitation of the current implementation.  So I hope this and
>   > similar bug reports lead to both more complete documentation and either
>   > a bug fix or, at some point, a more feature-rich implementation.
> 
> Not really, this is not a problem with --daemon, it's a problem in the
> ediff implementation that it evaluates ediff-window-setup-function at
> load time.  This is not appropriate anymore now when you can have both
> X11 and tty frames in the same emacs session.

Michael, could you please take care of this problem?

Thanks.

bug#2138: 23.0.60; --daemon and ediff-window-setup-function

[Chong Yidong]

Stephen Berman <stephen.berman@gmx.net> writes:

> 1. emacs -Q --daemon --eval "(require 'ediff)"
> 2. emacsclient -c
> 3. C-h v ediff-window-setup-function
> => ediff-setup-windows-plain

I've committed a fix to trunk.