Golang中的记录器功能失败

Question

I have what should be a very simple logger function but while the log file is created, nothing is written to it. I tried several different things but it continues to fail. The function is

func logger(logname string, message string) {
    logName := "../planner/log/" + logname + ".log"
    var file *os.File

    file, err := os.OpenFile(logName, os.O_APPEND|os.O_CREATE, 0755)
    if err != nil {
        fmt.Println("File", logName, "failed with error:", err)
    }

    //file.WriteString(message)
    fmt.Fprintf(file, message)
    fmt.Println("Wrote", message, "to", logName)
    file.Sync()
    file.Close()

    test, err := os.Stat(logName)
    size := test.Size()
    fmt.Println("File size is", size)
}

Answer 1

You are not getting anything in file because you are not opening it with os.WRONLY or os.RDWR. By default. os.OpenFile returns a buffer with only read permission. You might want to close your file with a defer in case the code panics with defer file.Close().