From: Ralf <lausianne@...>
Date: 2003-02-04T22:53:21+09:00
Subject: Re: tkgnuplot problem: fork() on win (popen3 for windows?)

nagai@ai.kyutech.ac.jp wrote:
 > Hi,
 >
 > From: nobu.nokada@softhome.net
 >>I guess qoutes surround command path are necessary.
 >>    gp = GnuplotProcess.new('"c:\program 
files\design\gnuplot\gp371w32\pgnuplot.exe"')
 >>Or, this seems better, put quotes in command for win32_popen4.
 >>   def _win32_open_process(*cmd)
 >>     require 'win32_popen'
 >>
 >>+    cmd.collect! {|s| /\s/ =~ s ? %{"#{s}"} : s}
 >>     IO.win32_popen4(cmd.join(' '))
 >>   end
 >
 > How foolish I am!
 > Ralf, could you try the test script after applying Nobu's patch
 > and report the result ?

BINGO!
The gnuplot process is started and the print'<ok>' command sent.
But ... the <ok> appears in the gnuplot window, and ...
in gnuplot.rb:initalize

     begin
       ret = ''
       @to_cmd.write "print '<OK>'\n"
       while s = @from_cmd.gets	# gets stuck here !!!
	break if s == "<OK>\n"	# because <ok> never arrives.
	ret << s
       end
     rescue Errno::EPIPE
       raise $!,'Lost gnuplot process (gnuplot argument error?)'
     end

So gnuplot maybe needs a parameter, so the window doesn't open, and the output
goes from gnuplot to "stdout" ?
We're close!
Thanks, Ralf.