From: ara.t.howard@...
Date: 2007-02-23T00:22:20+09:00
Subject: Re: IO.popen on Windows to filter stdout

On Thu, 22 Feb 2007, Harold Hausman wrote:

> Hello all,
>
> I've been googling and playing with this for a while, but I'm stuck and I
> figured I'd ask in case anyone's done this before.
>
> I'd like to use IO.popen, or something similar, to 'filter' the spew coming
> from another programs stdout. I think I understand that I can capture the
> stdout stream returned by IO.popen by using .readlines, etc... But it still
> seems that the sub process is writing the output directly to $stdout...
>
> Of course, this is on windows, so I don't have proper fork, etc...
>
> Is there a way to somehow "swallow" the stdout from the sub process so it
> doesn't make it directly to the ruby process' stdout?
>
> Thanks in advance for any insight,
> -Harold
>

probably the other process is writing to stderr.  try

   IO.popen( 'cmd 2>&1' ) do |pipe|
     pipe.each do |line|
       p line
     end
   end

alternatively, you may want to use systemu

   http://codeforpeople.com/lib/ruby/systemu

it's __very__ easy to block a process using IO.popen on windows.

regards.

-a
-- 
be kind whenever possible... it is always possible.
- the dalai lama