diff --git a/module/buffer.lua b/module/buffer.lua
index 3d64b1b..5b1e164 100644
--- a/module/buffer.lua
+++ b/module/buffer.lua
@@ -1,4 +1,4 @@
-local buffer = {}
+buffer = {}
 local metatable = {
  __index = buffer,
  __metatable = "file",
diff --git a/module/io.lua b/module/io.lua
new file mode 100644
index 0000000..59bf90a
--- /dev/null
+++ b/module/io.lua
@@ -0,0 +1,116 @@
+do
+io = {}
+
+function io.close(file)
+ return (file or io.output()):close()
+end
+
+function io.flush()
+ return io.output():flush()
+end
+
+function io.lines(filename, ...)
+ if filename then
+  local file, reason = io.open(filename)
+  if not file then
+   error(reason, 2)
+  end
+  local args = table.pack(...)
+  return function()
+   local result = table.pack(file:read(table.unpack(args, 1, args.n)))
+   if not result[1] then
+    if result[2] then
+     error(result[2], 2)
+    else -- eof
+     file:close()
+     return nil
+    end
+   end
+   return table.unpack(result, 1, result.n)
+  end
+ else
+ return io.input():lines()
+ end
+end
+
+function io.open(path, mode)
+ local stream, result = fs.open(path, mode)
+ if stream then
+  return buffer.new(mode, stream)
+ else
+  return nil, result
+ end
+end
+
+local fdt = {[0]="STDIN","STDOUT","STDERR"}
+local function getfh(fd)
+ return os.getenv(fdt[fd] or "FILE"..tostring(fd))
+end
+local function setfh(fd,fh)
+ os.setenv(fdt[fd] or "FILE"..tostring(fd),fh)
+end
+
+function io.stream(fd,file,mode)
+ checkArg(1,fd,'number')
+ assert(fd>=0,'fd must be >= 0. 0 is input, 1 is stdout, 2 is stderr')
+ if file then
+  if type(file) == "string" then
+   local result, reason = io.open(file, mode)
+   if not result then
+    error(reason, 2)
+   end
+   file = result
+  elseif not io.type(file) then
+   error("bad argument #1 (string or file expected, got " .. type(file) .. ")", 2)
+  end
+  setfh(fd,file)
+ end
+ return getfh(fd)
+end
+
+function io.input(file)
+ return io.stream(0, file, 'r')
+end
+
+function io.output(file)
+ return io.stream(1, file,'w')
+end
+
+function io.error(file)
+ return io.stream(2, file,'w')
+end
+
+function io.read(...)
+ return io.input():read(...)
+end
+
+function io.tmpfile()
+ local name = os.tmpname()
+ if name then
+  return io.open(name, "a")
+ end
+end
+
+function io.type(object)
+ if type(object) == "table" then
+  if getmetatable(object) == "file" then
+   if object.stream.handle then
+    return "file"
+   else
+    return "closed file"
+   end
+  end
+ end
+ return nil
+end
+
+function io.write(...)
+  return io.output():write(...)
+end
+
+function print(...)
+ for k,v in ipairs({...}) do
+  io.write(tostring(v).."\n")
+ end
+end
+end
diff --git a/module/oldio.lua b/module/oldio.lua
deleted file mode 100644
index abd3417..0000000
--- a/module/oldio.lua
+++ /dev/null
@@ -1,82 +0,0 @@
-do
-io = {}
-
-function io.type(fh)
- if type(fh) ~= "table" then return nil end
- if fh.state == "open" then
-  return "file"
- elseif fh.state == "closed" then
-  return "closed file"
- end
- return nil
-end
-
-function io.read(buf, n)
- n = n or buf
- buf = buf or io.input()
- print("bread",type(buf),n)
- if not buf.aread then return nil end
- if not buf.abmode then
-  buffer.write(buf,buf.fh:read(buf.m - buf.b:len()))
- end
- local rv = buffer.read(buf,n)
- buffer.write(buf,buf.fh:read(buf.m - buf.b:len()))
- return rv
-end
-function io.write(buf, d)
- d = d or buf
- buf = buf or io.output()
- print("bwrite",type(buf),d)
- if not buf.awrite then return nil end
- if buf.b:len() + d:len() > buf.m then
-  buf.fh:write(buffer.read(buf,buf.m))
- end
- local rv = buffer.write(buf,d)
- if not buf.abmode then
-  buf.fh:write(buffer.read(buf,buf.m))
- end
- return rv
-end
-
-function io.close(fh)
- fh.fh.close()
- fh.state = "closed"
-end
-
-function io.flush()
-end
-
-function io.open(fname,mode)
- mode=mode or "r"
- local buf = buffer.new()
- buf.fh, er = fs.open(fname,mode)
- if not buf.fh then
-  error(er)
- end
- buf.state = "open"
- buf.aread = mode:match("r")
- buf.awrite = mode:match("w") or mode:match("a")
- setmetatable(buf,{__index=io})
- return buf
-end
-
-function print(...)
- for k,v in ipairs({...}) do
-  io.write(string.format("%s\n",tostring(v)))
- end
-end
-
-io.stdin = io.open("/dev/null")
-io.stdout = io.open("/dev/null","w")
-
-function io.input(fname)
- if not fname then return os.getenv("STDIN") or io.stdin end
- os.setenv("STDIN",io.open(fname))
-end
-
-function io.output(fname)
- if not fname then return os.getenv("STDOUT") or io.stdout end
- os.setenv("STDOUT",io.open(fname,"w"))
-end
-
-end