Go chan write to a file structure

chan requires two processes, a write, a read, are separated,

package main

import (
   "bufio"
   "fmt"
   "math/rand"
   "os"
   "strings"
   "sync"
   "time"
)

type (
   cdnfileinfo struct {
      filename string
      buf      []byte
      sync.RWMutex
      wrtype int
      serr   string
   }
   fileWrok interface {
      isDirExtxit(path string) int
      Writefile(b *backset)
      Readfile(b *backset)
      Randfilename(b *backset)
   }
   fileWorkint interface {
      Randfilename(b *backset)
   }

    Workout struct {
      fileWrok
   }
      workInt struct {
       fileWorkint
     }
   backset struct {
      ducks chan cdnfileinfo
   }

)

func (fi *Workout) isDirExtxit(path string) int {
   finfo, er := os.Stat(path)
   if er != nil {
      return 0
   }
   if finfo.IsDir() {
      return 1
   } else {
      return 2
   }

}
func (fi *workInt)Randfilename(b *backset)  {
   for {
      duck := cdnfileinfo{
         filename: "D:/Text/log" + fmt.Sprint(rand.Intn(999999)) + ".txt",
         wrtype:   2,
         buf:      []byte("添加测试"),
      }
      fmt.Printf("type:%d   filename:%s \n", duck.wrtype, duck.filename)
      b.ducks <- duck
      time.Sleep(time.Second)
   }
}


func (fi *Workout) Writefile(b *backset)  {
   for {
      duck, _ := <-b.ducks
      pos := strings.LastIndex(duck.filename, "/")
      path := duck.filename[0 : pos+1]
      switch fi.isDirExtxit(path) {
      case 0:
         {
            er := os.Mkdir(path, os.ModePerm)
            if er != nil {
                continue
            }
         }
      case 2:
         {
            continue
         }

      }

      f, er := os.OpenFile(duck.filename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
      if er != nil {

      }
      fbuf := bufio.NewWriter(f)
      fbuf.Write(duck.buf)
      fbuf.Flush()
      fmt.Printf("type:%d   filename:%s \n", duck.wrtype, duck.filename)
   }
}
func (fi *Workout) Readfile(b *backset) error {
   duck,_:= <- b.ducks
   _, er := os.Stat(duck.filename)
   if er != nil {
      return nil
   }
   sf, er := os.Open(duck.filename)
   if er != nil {
      return er
   }
   rbuf := bufio.NewReader(sf)
   n, er := rbuf.Read(duck.buf)
   if er != nil {
      return nil
   }
   if n == 0 {
      return fmt.Errorf("读取文件为空")
   }
   return nil
}

func main() {
   wa := new(sync.WaitGroup)

   p := new(workInt)
    c := new(Workout)
   b := &backset{
       ducks: make(chan cdnfileinfo),
   }

   wa.Add(2)
   go func() {
      p.Randfilename(b)
      wa.Done()
   }()
    go func() {
       c.Writefile(b)
       wa.Done()
   }()

   wa.Wait()

}