Using system() to execute a script outside of Rails but in a directory in the Rails app...

I'm trying to hack around a previously mentioned RMagick problem,
confirmed to exist inside of Rails but not outside.
Thus, I'd like to call a Ruby script from with in a Rails controller.
Like so:
system("#{RAILS_ROOT}/public/images/thumb_and_comp.rb",
"#{@asset.file_name}")

But it never seems to get executed.
Permissions are set to 755 on the script.
Any suggestion?

If you're just trying to do thumbnails, better to look at how
file_column or a similar plugin accomplish that than to shell out to
a different process. Rails is a one-in-one-out pipe, so blocking
requests on a shell process could really screw up your performance.

I know Rails is a single threaded process, because Ruby is as well.
But at this point even the maintainer of RMagick (who I've been
talking to a lot the last few days) is mystified by how my thumbs can
be correct when run from a straight Ruby script on the same system,
but through Rails it gets screwed up.

Well, I dunno, but I used file_column on one of my sites that's been
happily purring away and the relevant code is:

img = ::Magick::Image::read(absolute_path).first
resize_image(img, version_options[:geometry], absolute_path(name))

Where version_options[:geometry] is, as you might expect, the
geometry to resize to a thumbnail. Are you doing something different?