帮忙看看为什么会死锁

```go package main import ( "bufio" "fmt" "io" "log" "os" "strconv" "time" ) func readData(bfRd io.Reader, dataChan chan []byte, endChan chan error) { buf := make([]byte, 100) for { n, err := bfRd.Read(buf) if err != nil { endChan <- err return } fmt.Printf("read data %s size \n", strconv.Itoa(n)) dataChan <- buf[:n] } } func main() { file, err := os.Open("/Users/abin/data/e/dev1/server/src/lab/lab1.go") if err != nil { log.Fatalln(err) } var data []byte bfRd := bufio.NewReader(file) var dataChan = make(chan []byte) var endChan = make(chan error) go readData(bfRd, dataChan, endChan) var d []byte L: for { select { case err := <-endChan: fmt.Println(err) break L case d = <-dataChan: data = append(data, d...) case <-time.After(time.Second): fmt.Println("timeout") break L default: fmt.Println("channel cannot use") } } fmt.Println(string(data)) } ```

你上面的代码真的不忍看，漏洞百出，我修改过的，你看下，地址：https://play.golang.org/p/-qntkhCVVtA

基于你的代码修改，首先`fmt.Println(<-endChan)`会造成`deadlock`，然后`select`中的`break`并不能跳出外层`for`循环，代码如下： ```go package main import ( "bufio" "fmt" "io" "log" "os" "strconv" "time" ) func readData(bfRd io.Reader, dataChan chan []byte, endChan chan error) { buf := make([]byte, 100) for { n, err := bfRd.Read(buf) if err != nil { endChan <- err return } fmt.Printf("read data %s size \n", strconv.Itoa(n)) dataChan <- buf } } func main() { file, err := os.Open("client.go") if err != nil { log.Fatalln(err) } var data []byte bfRd := bufio.NewReader(file) var dataChan = make(chan []byte) var endChan = make(chan error) go readData(bfRd, dataChan, endChan) L: for { select { case err := <-endChan: fmt.Println(err) break L case <-dataChan: data = append(data, <-dataChan...) case <-time.After(time.Second): fmt.Println("timeout") break L default: fmt.Println("channel cannot use") } } fmt.Println(string(data)) } ```