Re: FAQ: gnuplot vs. emacs' compile command

Re: FAQ: gnuplot vs. emacs' compile command

[Kim F. Storm]

Did anyone actually look at this bug back in May ?
FYI, I have included the text at the referenced link here.

Dan Jacobson <jidanni@dman.ddts.net> writes:

> Fellas, the gnuplot team may have found ugly emacs process bugs, see
> <...>
> 

: Dan Jacobson <jidanni@dman.ddts.net> wrote:
: 
: > Using emacs -eval '(compile "make")'
: > With: echo "plot 'file';pause -1"|gnuplot -persist
: > just flashes the graph for a split second.
: 
: So let's get into dissecting this further.  The first candidate to
: remove is 'make'.  It doesn't really do anything useful in this whole
: setup, so we might as well get rid of it.  Let's replace it by a shell
: script doing the same things.  And while at it, let's get rid of the
: separate data file, too:
: 
: --- gpaction ---
: gnuplot -persist <<EOS
:  plot '-'
:    1 1
:    2 2
:   e
: EOS
: ---- end ---
: 
: sh gpaction                                 # does the plot and returns
: emacs -eval '(compile "sh gpaction")'       # doesn't plot, but returns
: emacs -eval '(shell-command "sh gpaction")' # plot, but no return
: 
: For the latter, emacs is unresponsive --- it's obviously waiting for
: something to happen, which doesn't.  Only after you terminate the
: gnuplot graph window (key 'q' into it), or press Ctrl-G in emacs to
: forcibly break out of the wait loop, it will continue.
: 
: During that pause, look at the output from 'ps jx' and you'll find
: that gnuplot_x11 is an orphan --- i.e. it's the only surviving process
: in its process group.  In "shell-command", emacs apparently doesn't
: kill it, whereas in "compile", it probably does.
: -- 
: Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
: Even if all the snow were burnt, ashes would remain.

-- 
Kim F. Storm  http://www.cua.dk

Re: FAQ: gnuplot vs. emacs' compile command

[Stefan Monnier]

> Did anyone actually look at this bug back in May ?
> FYI, I have included the text at the referenced link here.

What is the bug exactly?
My understanding is of the problem:
when Emacs exits, gnuplot is killed because its stdout is connected to
Emacs (i.e. it receives a SIGPIPE or SIGHUP or somesuch).


        Stefan


> Dan Jacobson <jidanni@dman.ddts.net> writes:

>> Fellas, the gnuplot team may have found ugly emacs process bugs, see
>> <...>
>> 

> : Dan Jacobson <jidanni@dman.ddts.net> wrote:
> : 
> : > Using emacs -eval '(compile "make")'
> : > With: echo "plot 'file';pause -1"|gnuplot -persist
> : > just flashes the graph for a split second.
> : 
> : So let's get into dissecting this further.  The first candidate to
> : remove is 'make'.  It doesn't really do anything useful in this whole
> : setup, so we might as well get rid of it.  Let's replace it by a shell
> : script doing the same things.  And while at it, let's get rid of the
> : separate data file, too:
> : 
> : --- gpaction ---
> : gnuplot -persist <<EOS
> :  plot '-'
> :    1 1
> :    2 2
> :   e
> : EOS
> : ---- end ---
> : 
> : sh gpaction                                 # does the plot and returns
> : emacs -eval '(compile "sh gpaction")'       # doesn't plot, but returns
> : emacs -eval '(shell-command "sh gpaction")' # plot, but no return
> : 
> : For the latter, emacs is unresponsive --- it's obviously waiting for
> : something to happen, which doesn't.  Only after you terminate the
> : gnuplot graph window (key 'q' into it), or press Ctrl-G in emacs to
> : forcibly break out of the wait loop, it will continue.
> : 
> : During that pause, look at the output from 'ps jx' and you'll find
> : that gnuplot_x11 is an orphan --- i.e. it's the only surviving process
> : in its process group.  In "shell-command", emacs apparently doesn't
> : kill it, whereas in "compile", it probably does.
> : -- 
> : Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
> : Even if all the snow were burnt, ashes would remain.

> -- 
> Kim F. Storm  http://www.cua.dk



> _______________________________________________
> Emacs-devel mailing list
> Emacs-devel@gnu.org
> http://mail.gnu.org/mailman/listinfo/emacs-devel

Re: FAQ: gnuplot vs. emacs' compile command

[Kim F. Storm]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

> > Did anyone actually look at this bug back in May ?
> > FYI, I have included the text at the referenced link here.
> 
> What is the bug exactly?

I don't know.  Dan, can you elaborate?

> My understanding is of the problem:
> when Emacs exits, gnuplot is killed because its stdout is connected to
> Emacs (i.e. it receives a SIGPIPE or SIGHUP or somesuch).

.. which emacs cannot do anything about.

> 
> 
>         Stefan
> 
> 
> > Dan Jacobson <jidanni@dman.ddts.net> writes:
> 
> >> Fellas, the gnuplot team may have found ugly emacs process bugs, see
> >> <...>
> >> 
> 
> > : Dan Jacobson <jidanni@dman.ddts.net> wrote:
> > : 
> > : > Using emacs -eval '(compile "make")'
> > : > With: echo "plot 'file';pause -1"|gnuplot -persist
> > : > just flashes the graph for a split second.
> > : 
> > : So let's get into dissecting this further.  The first candidate to
> > : remove is 'make'.  It doesn't really do anything useful in this whole
> > : setup, so we might as well get rid of it.  Let's replace it by a shell
> > : script doing the same things.  And while at it, let's get rid of the
> > : separate data file, too:
> > : 
> > : --- gpaction ---
> > : gnuplot -persist <<EOS
> > :  plot '-'
> > :    1 1
> > :    2 2
> > :   e
> > : EOS
> > : ---- end ---
> > : 
> > : sh gpaction                                 # does the plot and returns
> > : emacs -eval '(compile "sh gpaction")'       # doesn't plot, but returns
> > : emacs -eval '(shell-command "sh gpaction")' # plot, but no return
> > : 
> > : For the latter, emacs is unresponsive --- it's obviously waiting for
> > : something to happen, which doesn't.  Only after you terminate the
> > : gnuplot graph window (key 'q' into it), or press Ctrl-G in emacs to
> > : forcibly break out of the wait loop, it will continue.
> > : 
> > : During that pause, look at the output from 'ps jx' and you'll find
> > : that gnuplot_x11 is an orphan --- i.e. it's the only surviving process
> > : in its process group.  In "shell-command", emacs apparently doesn't
> > : kill it, whereas in "compile", it probably does.
> > : -- 
> > : Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
> > : Even if all the snow were burnt, ashes would remain.
> 
> > -- 
> > Kim F. Storm  http://www.cua.dk
> 
> 
> 
> > _______________________________________________
> > Emacs-devel mailing list
> > Emacs-devel@gnu.org
> > http://mail.gnu.org/mailman/listinfo/emacs-devel
> 
> 

-- 
Kim F. Storm <storm@cua.dk> http://www.cua.dk

Re: FAQ: gnuplot vs. emacs' compile command

[Dan Jacobson]

I recall the gnuplot author had a lot of response.
I am only good at finding bugs, not following up.
If next time I run into a bug, you'll be sure to hear from me.