local f1 = io.open("filename.txt", "a+")
local f2 = io.open("filename.txt", "a+")
f1:write("Some text")
f2:write("Another text")
f1:close()
f2:close()

function rec_big_data(file_path, value, paper)
    rn = rn or {}
    rn[paper] = rn[paper] or {}
    if file_path~=rn[paper].file_path then
        if rn[paper].handler then
            rn[paper].handler:close()
        end
        rn[paper].handler = io.open(file_path, "a+")
        if rn[paper].handler then
            rn[paper].handler:setvbuf("no")        --<<<--- отключение кэша
            rn[paper].file_path = file_path
        else
            mm("QL:open file error "..file_path)
        end
    end
    if rn[paper].handler then
        rn[paper].handler:write(value.."\n")
    end
end

            rn[paper].handler:setvbuf("full", 1024*1024)

count[paper]=(count[paper] or 0)+1
   if count[paper]==100 then
      rn[paper].handler:flush()
      count[paper]=0
   end

rn = rn or {}
rn[paper] = rn[paper] or {}
if file_path~=rn[paper].file_path then
    if rn[paper].handler then
        rn[paper].handler:close()
    end
    rn[paper].handler:io.open(file_path, "a+")
    if rn[paper].handler then
        rn[paper].file_path = file_path
    else
        mm("QL:open file error "..file_path)
    end
end
if rn[paper].handler then
    rn[paper].handler:write(value.."\n")
end

function rec_big_data(file_path,value)         
if rn==nil then rn={} end         
   if file_open==nil then file_open={} end
      if file_open[file_path]==nil then
         rn[file_path]=io.open(file_path,"a+")
         file_open[file_path]=true
         mm("QL:open file "..file_path)
      end
      rn[file_path]:write(value.."\n")
      rn[file_path]:flush()
end