I don't think so. the while (<RUN>) assigns the line from the RUN filehandle to $_, then you print out $line (which hasn't been assigned anything in this snippet). I don't think that's what the OP wants.
Comment on Re^2: Passing an array into an open command
I was trying to identify that what he wanted to do was run through his <RUN> and print something-- I just used his $line variable without thinking about what that does.
Oh well. At least I knew his while ($line= <RUN>... was a problem. I may get the hang of this yet. Thanks for the feedback.