Strip Top Blank Lines of a File

#!/usr/bin/env ruby
# Usage: ./strip-top-blanks.rb "dir/file.ext"
if ARGV.length>0
  filename=ARGV[0]

  file=File.new filename,'r'
  lines=file.readlines
  file.close

  file=File.new filename,'w'
  hit=false
  lines.each do |line|
    if hit || !line.strip.empty?
      file.puts line
      hit=true
    end
  end
  file.close
end