What are the filenames seperated with. I.e. is there a space between each filename in the textarea?

Let's assume that this is the case. What you need is an array of all the filenames listed in the textarea. You need to read in each line seperated by the \n and then split the line by spaces. I.e.

@line = split/\s/,$line_read_in;
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foreach my $filename (@line) {
    push (@list_of_filenames, $filename)
}
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