Added example of context on golang

examples/golang/cource/05h_context.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+	"fmt"
+	"context"
+	"time"
+)
+
+func sendData(ctx context.Context, num int) {
+	timer := time.NewTimer(time.Duration(num) * time.Second)
+
+	select {
+	case <-ctx.Done():
+		fmt.Printf("Gorutine $%v canceled\n", num)
+		return
+	case <-timer.C:
+		fmt.Printf("Data was send by #%v\n", num)
+	}
+}
+
+func main() {
+	ctx := context.Background()
+
+//	ctxtype, cancel := context.WithCancel(ctx)
+	ctxtype, _ := context.WithTimeout(ctx, 2 * time.Second)
+
+
+	for i := 1; i < 6; i++ {
+		go sendData(ctxtype, i)
+	}
+
+//	time.Sleep(2 * time.Second)
+//	cancel()
+	time.Sleep(1 * time.Second)
+}