Updated README.md with exit code sample

README.md

@@ -251,6 +251,28 @@ app.Commands = []cli.Command{
 ...
 ```
 
+### Exit code
+
+It is your responsability to call `os.Exit` with the exit code returned by
+`app.Run`
+
+```go
+package main
+
+import (
+  "os"
+  "github.com/codegangsta/cli"
+)
+
+func main() {
+  exitCode, err := cli.NewApp().Run(os.Args)
+  if err != nil {
+    log.Println(err)
+  }
+  os.Exit(exitCode)
+}
+```
+
 ### Bash Completion
 
 You can enable completion commands by setting the `EnableBashCompletion`