在iOS上，从实时流中播放视频，同时将流保存到磁盘

I've been looking into this topic for a while now and I can't really figure out how I could achieve this. Let's say we have a video from an HTTP Stream and I want to be able to play that video in my app, and at the same time the video is also persisted on the disk. I know I can play videos with the I've been looking into this topic for a while n