--
-- extract file name list by DOS "dir" command
--
filename = "filelist.txt"
filename_out = "filelist_out.txt"
fileext = "lua"
os.execute("dir /b *."..fileext.." > "..filename)

fr = io.open(filename)
fw = io.open(filename_out, "w")
for line in fr:lines() do
  --i:position of 1st found string
  --j:position of 2nd found string
  --k:substring of 1st found string
  --l:substring of 2nd found string
  i,j,k,l=string.find(line, "(.+)%.(.+)")
  print(line.." "..i.." "..j..":"..k..":"..l)
  fw:write(k.."\n")
end
fr:close()
fw:close()