5-4 buffer is written

main Package Penalty for 

Import ( 
    " the BUFIO " 
    " fmt " 
    " os " 
) 

// to create additional write or record write cover to open a file, 
/ * 
steps 
to open a file to determine the results, create a writer, call writer method. Close file 
* / 
FUNC main () { 
    // If the file does not exist, create a write-only mode + + append data to generate the file permissions are 666 
    File, ERR: = os.OpenFile ( " C: / the Users / Administrator / Desktop / test .txt " , os.O_CREATE | os.O_WRONLY | os.O_APPEND, 0666 ) 

    // If the file does not exist, create and write-only mode and overwrite files
     // file, ERR: = os.OpenFile (" C: / the Users / Administrator / Desktop / test .txt ", os.O_CREATE | os.O_WRONLY | os.O_TRUNC, 0666) 
    IF ERR =!{nil 
        fmt.Println ( " file open failure, ERR = " , ERR)
         return 
    } 
    the defer FUNC () { 
        File.close () 
        fmt.Println ( " file closed " ) 
    } () 
    Writer: = bufio.NewWriter (File ) 

    // write data in batches, write string 
    writer.WriteString ( " a \ n- " ) 
    writer.WriteString ( " B \ n- " ) 
    writer.WriteString ( " C \ n- " ) 
    writer.WriteString ( " D \ the n- " )

    // write word 
    writer.WriteRune ( ' you ' ) 
    
    writer.Write ([] byte { 123 })
     // flushed to disk 
    writer.Flush () 

}