From: Robert Klemme <bob.news@...>
Date: 2003-02-25T17:52:08+09:00
Subject: Re: Threads, pipes, popen, whatever


A simple solution seems to be this: Write a shell script like
#! /bin/sh -f
echo "$*" | your_filter
# or echo "$1" | your_filter

Then, from within ruby

result = system("your_script", "a string")
# result is boolean

Normally you would use IO.popen but I can't see a way to access the exit
status of the process directly.  Something like this comes to mind, but I
could not convice "popen" to behave like documented, because "-" is not
treated as documented

def f( word )
  result = nil

  IO.popen("-", "r+") do |io|
    if io
      # parent process
      io.puts word
      result = io.readlines.shift.chomp
    else
      # child process
      puts system("more")
    end
  end

  result == "true"
end

Any other hints?

    robert

"Albert Wagner" <alwagner@tcac.net> schrieb im Newsbeitrag
news:20030224054714.04780080.alwagner@tcac.net...
> I have never before had occasion to do the following kind of problem, so
> I haven't a clue where to start.  I have a C filter that accepts a
> string on stdin and returns a boolean based on it's analysis of the
> string.  In a ruby program I want to pass a list of strings, one at a
> time, to the filter and take appropriate action based on each return
> value.  Could someone point me in the right direction? I have never
> worked with threads or pipes before.
>
> Albert
>