From: Shashank Date <sdate@...>
Date: 2002-12-19T14:14:31+09:00
Subject: Re: automating script for a command line utility

Per nobu's suggestion, this is what I did:

    check = IO.popen("ruby c:/ruby/bin/irb.rb",'w+')
    check.puts("STDOUT.sync = true")
    check.puts("puts $:")
    check.readlines.each { |line| puts line unless line =~ 'nil' }
    check.close_write
    check.readlines.each { |line| puts line unless line =~ 'nil' }

But the program seemed to hang.
So I killed it (using CTRL+Break in TextPad) and I got this:

Interrupted!

and after a couple of minutes ...

    C:/ruby/lib/ruby/1.7/irb.rb:234:in `write': Invalid argument
(Errno::EINVAL)
     from C:/ruby/lib/ruby/1.7/irb.rb:234:in `print'
     from C:/ruby/lib/ruby/1.7/irb.rb:234:in `signal_handle'
     from C:/ruby/lib/ruby/1.7/irb.rb:66:in `start'
     from C:/ruby/lib/ruby/1.7/irb.rb:65:in `call'
     from C:/ruby/lib/ruby/1.7/irb/input-method.rb:49:in `gets'
     from C:/ruby/lib/ruby/1.7/irb/input-method.rb:49:in `gets'
     from C:/ruby/lib/ruby/1.7/irb.rb:130:in `eval_input'
     from C:/ruby/lib/ruby/1.7/irb.rb:129:in `signal_status'
      ... 14 levels...
     from C:/ruby/lib/ruby/1.7/irb.rb:70:in `start'
     from C:/ruby/lib/ruby/1.7/irb.rb:69:in `catch'
     from C:/ruby/lib/ruby/1.7/irb.rb:69:in `start'
     from c:/ruby/bin/irb.rb:13

    Tool completed with exit code 4

Please help.

Thanks very much !

-- shanko

<nobu.nokada@softhome.net> wrote in message
news:200212190443.gBJ4hLb24230@sharui.nakada.kanuma.tochigi.jp...
> Hi,
>
> At Thu, 19 Dec 2002 13:14:07 +0900,
> Shashank Date wrote:
> > Is there a way to check.puts each command and then immediately read the
> > lines of output ?
>
> Try to send "STDOUT.sync = true" line first.  This is because
> the child process buffers stdout.  In many UNIX, using pseudo
> TTY tells processes to not buffer output, but Windows has no
> this feature or similar.
>
> I remember I wrote about this, regarding cygwin and DOS prompt
> issue.
>
> > I think IO#popen3 might do this, but it is not available on Windows.
>
> Correct, but impossible as OS doesn't support it.
>
> --
> Nobu Nakada
>