From: Bill Atkins <batkins57@...>
Date: 2005-08-11T23:37:05+09:00
Subject: Re: Threading on Win32 - at an impasse

Sure.  This solution might not work for everyone, because fortunately
I don't really have to do much interprocess communication aside from
being able to start and stop children at will.  So I have a simulation
class:

require 'win32/process'

class Simulation
  .... blah blah blah

  def start
    @pid = Process.run "ruby bin/run_device.rb #@dev_name #@name"
  end

  def kill
    Process.kill 9, @pid if @pid
    @pid = nil
  end

   .......blah blah blah
end

And the bin/run_device.rb file loads up the appropriate simulation and
does its thing in the background.  run_device.rb is the important part
- it is more or less my answer to Win32's lack of fork; it loads the
library files it needs and then starts up the simulator, so it's as if
I've forked the process, but not really. :)  run_device.rb's code is
long and not too interesting (and application-dependent in any case),
so I won't post it here.

Process.run is a custom function that Does The Right Thing based on
what OS the program is running on:

module Process
  def self.run app
    if RUBY_PLATFORM =~ /win32/
      puts "calling create"
      Process.create :app_name => app
    else
      puts "calling fork"
      fork do
        exec app
      end
    end
  end
end

If only Microsoft would implement fork/exec........

Sigh.

Hope that helps,
Bill

On 8/11/05, Ara.T.Howard <Ara.T.Howard@noaa.gov> wrote:
> On Thu, 11 Aug 2005, Bill Atkins wrote:
> 
> > All right, just in case anyone googles this later on, I was able to
> > get my application working with the help of win32-process.  I used
> > separate processes instead of threads, because calling gets on stdin
> > seems to block all threads no matter what.
> >
> > So it seems like separate processes are the way to go, at least until
> > Ruby 2.0 (or whenever it gets native threads).
> 
> can you post a baby example?
> 
> cheers.
> 
> -a
> --
> ===============================================================================
> | email :: ara [dot] t [dot] howard [at] noaa [dot] gov
> | phone :: 303.497.6469
> | Your life dwells amoung the causes of death
> | Like a lamp standing in a strong breeze.  --Nagarjuna
> ===============================================================================
> 
> 
> 


-- 
Bill Atkins