读取文件前面若干行并保存到文件

files = Dir.glob('*.csv')
files.each do |f|
 src = File.open(f, "r")
 header = src.readline.chop
 out = File.new("header/#{f}", "w")
 out.puts(header)
 i = 0
 while !src.eof? do
   out.puts(src.readline)
   i += 1
   break if i > 100
 end
 src.close
 out.close
end