增加 Golang Chan 超时.

Signed-off-by: chen.yang <chen.yang@yuzhen-iot.com>

Software/Development/Language/Go/Basic/Chan/Golang_Chan_超时.md

@@ -0,0 +1,28 @@
+# Golang Chan 超时
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+)
+
+var ch chan int = make(chan int, 1)
+
+func main() {
+    go aaa()
+
+    select {
+    case <-ch: //拿到锁
+        fmt.Println("call")
+    case <-time.After(5 * time.Second): //超时5s
+        fmt.Println("5 sec call")
+    }
+}
+
+func aaa() {
+    time.Sleep(time.Second * 3)
+    ch <- 1
+}
+```