golang bad file descriptor问题的解决方法

package main

import (
 "os"
 "fmt"
)

func main() {
 file, err := os.Open("a.txt")
 if err != nil {
  fmt.Println(err)
 }
 defer file.Close()

 content:=[]byte("Go is an open source programing language that makes it easy to build simple,reliable,and efficient software")
 _, err = file.Write(content)
 if err != nil {
  fmt.Println(err)
 }
}

func Open(name string) (*File,error) {
 return OpenFile(name, O_RDONLY, 0)
}

package main

import (
 "os"
 "fmt"
)

func main() {
 file, err := os.OpenFile("a.txt", os.O_APPEND|os.O_WRONLY, os.ModeAppend)
 if err != nil {
  fmt.Println(err)
 }
 defer file.Close()

 content:=[]byte("Go is an open source programing language that makes it easy to build simple,reliable,and efficient software")
 _, err = file.Write(content)
 if err != nil {
  fmt.Println(err)
 }
}