From: ara.t.howard@...
Date: 2006-11-17T07:48:22+09:00
Subject: Re: Another IO.popen question ...

On Fri, 17 Nov 2006, Adam Groves wrote:

> Hi Joel,
>
> thanks for the speedy reply! The problem is, I need to pass on a file
> object (which has been uploaded from a web page form) to 'convert' and
> not just a path. I should have made this clearer in my original post.
>
> Any ideas?

you can pass convert files on stdin.  you need somthing like

   stdin = file_object.read

   cmd = " convert - png:- "  # input on stdin, output to stdout

   stdout =
     IO.popen( cmd, 'r+' ) do |pipe|
       pipe.write stdin
       pipe.close_write
       pipe.read
     end

   abort "cmd <#{ cmd }> failed" unless $? == 0

   open the_png, 'w' do |f|
     f.write stdout
   end

regards.

-a
-- 
my religion is very simple.  my religion is kindness. -- the dalai lama