Re: gnuplot talk

[Joao Cardoso]

Daniel Heiserer wrote:
> 
> How is the interaction
> between gnuplot and octave done?
> Does octave write to a fifo-pipe which is gnuplots stdin
> or how does it work?

File based. That's why you can type `replot' and everything works. If it
were pipe based gnuplot wouldn't replot. Commands are send through a
pipe, however.

> ls -l /usr/tmp/oct-*|wc -l
     19

 And still more:

> ps...

  pid  ppid
 28138 23986  0 19:53:59   ttyp2    00:00:00 octave
 28139 28138  0 19:54:02   ttyp2    00:00:00 sh -c gnuplot
 28140 28139  0 19:54:02   ttyp2    00:00:00 gnuplot
 28141 28140  0 19:54:02   ttyp2    00:00:00 sh -c gnuplot_x11
 28142 28141  0 19:54:02   ttyp2    00:00:00 gnuplot_x11

That's why plplot_octave is beautiful (and plreplot() a mess)

> 
> How big is the deal to make that bidirektional
> and give octave not only a "write_to_plottool" "FILE *"
> but even a "read_from_plottool" device.

This has been asked several times. John Eaton answer has always been: do
it and submit a patch (if I remember correctly).

Joao

-- 
Joao Cardoso                |   e-mail: address@hidden
INESC, R. Jose Falcao 110   |   tel:    + 351 2 2094322
4050 Porto, Portugal        |   fax:    + 351 2 2008487



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