Validating Receipts Locally

Perform receipt validation immediately after your app is launched, before displaying any user interface or spawning any child processes. Implement this check in the main function,
before the NSApplicationMain function is called. For additional security, you may repeat this check periodically while your application is running.

在应用启动之后，用户界面展示或子进程执行之前就要开始验证收据是否准确。验证方法要在main函数中，NSApplicationMain函数调用之前实现。为了更加安全，你可能要在应用运行过程中重复执行验证。

Validating Receipts Locally