Golang bufio WriteByte 无效

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我有一个小问题。我正在尝试让一个程序从文件中读取并在不同的文件中写入完全相同的内容。我已经让它工作了，但我认为如果我利用 goroutine 稍微修改它，它应该会更快。我将阅读和写作分成不同的功能，并尝试让它们进行交流。它们似乎可以正常通信，但写入函数似乎实际上并未向目标文件写入任何内容。问题是，当我选择一个比简单的短文本文件大得多的文件时，它确实会写入，但不是整个文件，它会丢失一些东西。 谁能确切地告诉我这怎么会出错？我的代码在这里：

func main() {
    // Creating channels
    messages := make(chan byte)
    status := make(chan bool)
    finished := make(chan bool)
    fmt.Printf("Reporting from main thread. Created the channels, go routines will follow.\n")
    go readFileRoutine("file", messages, status, finished)
    fmt.Printf("Reporting from main thread, readFileRoutine has been let go.\n")
    go writeFileRoutine("destination", messages, status)
    fmt.Printf("Reporting from main thread, writeFileRoutine has been let go. Waiting on status message\n")
    <-finished
    close(status)
    fmt.Printf("Success!\n")
}

func readFileRoutine(filename string, messages chan byte, status chan bool, finished chan bool) {
    file, err := os.Open(filename)
    check(err)
    buff := bufio.NewReader(file)
    fmt.Printf("Reporting from readFileRoutine, initialised. Will start reading now!\n")
    for {
        byti, err := buff.ReadByte()
        fmt.Printf("Read character %c\n", byti)
        if err == io.EOF { //If EOF break for loop and finish off
            readFinished = true
            break
        }
        <-status         // Waiting for status message from writeFileRoutine
        messages <- byti //Putting next message on channel, then buffering next character

    }
    fmt.Printf("Reporting from readFileRoutine, finished reading and putting messages on channel, will now wait on writer to finish\n")
    //fmt.Printf("Reporting from readFileRoutine, finished with reading. Closing file and messages channel now\n")
    file.Close()
    <-status
    fmt.Printf("Reporting from readFileRoutine, moving on to closing messages channel. Received status from writer correctly!\n")
    close(messages)
    <-status
    fmt.Printf("Reporting from readFileRoutine, closed messages channel, will report status on the finished channel.\n")
    finished <- true
}

func writeFileRoutine(filename string, messages chan byte, status chan bool) {
    file, err := os.Create(filename) // Creates a new file
    check(err)
    buf := bufio.NewWriter(file) //New file writer
    fmt.Printf("Reporting from writeFileRoutine, initialised. Will start writing now!\n")
    status <- true
    for readFinished == false {
        bit := <-messages // Wait for receiving
        fmt.Printf("Received message %c\n", bit)
        buf.WriteByte(bit)
        fmt.Printf("Written byte %c\n", bit)
        status <- true //Sending status to readFileRoutine, done writing and waiting for next character
    }
    fmt.Printf("Reporting from writeFileRoutine, read all messages from reader and put them in a file\n")
    file.Close()
    fmt.Printf("Reporting from writeFileRoutine, closed file, will put true on status channel and exit\n")
    status <- true
}

解决方案

正如 Martin 在评论中指出的那样，我只是忘记了 Writer.Flush() 函数。我将 buf.Flush() 放在 buf.WriteByte(bit) 之后，并修复了它。

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