Added part of golang course, channels

examples/golang/05c_channels.go

@@ -0,0 +1,72 @@
+package main
+
+import "fmt"
+import "time"
+import "runtime"
+
+func readChan(ch chan int) {
+	value := <-ch
+	fmt.Println("CHAN VALUE: ", value)
+}
+
+func writeChan(ch chan <- int) {
+	for i := 1; i <= 5; i++ {
+		ch<- i
+	}
+	close(ch)
+}
+
+func writeSelect(ch chan<- int) {
+	ch<- 1
+}
+
+func readSelect(ch, quit <-chan int) {
+	for {
+		select {
+		case x := <-ch:
+			fmt.Println("ch3 = ", x)
+		case <-quit:
+			fmt.Println("quit")
+			return
+		default:
+			fmt.Println("default")
+		}
+	}
+}
+
+func main() {
+	fmt.Println("START MAIN")
+	var ch chan int
+	var ch2 chan int
+
+// Buffered and unbuffered channel
+	ch = make(chan int, 1)
+//	ch = make(chan int)
+
+	ch<- 77
+	go readChan(ch)
+	ch<- 111
+
+	time.Sleep(1 * time.Second)
+
+// for
+	ch2 = make(chan int)
+	go writeChan(ch2)
+
+	for i := range ch2 {
+		fmt.Println("chan i = ", i)
+	}
+
+// select 
+	ch3 := make(chan int)
+	quit := make(chan int)
+
+	go readSelect(ch3, quit)
+
+	go writeSelect(ch3)
+	runtime.Gosched()
+	go writeSelect(quit)
+
+
+	fmt.Println("END MAIN")
+}