download a 'package' to iOS

I have an iOS app, and at certain times I need to download a package containing multiple items (ie: images, and so开发者_运维知识库me txt files). I always only want to download all or none. I don't want to get partial downloads (ie: I don't want to be in a situation where I only download 2 of 4 images).

So, is there a way that I can package all the items into a single file, then download that file, and extract it within my iOS app? I'm hoping there's a native way of doing this that does't require me to write some sort of archiver.

Thanks!

Sunny

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It's not "native" to iOS, but you can use the objective-zip library to unzip a Zip archive: http://code.google.com/p/objective-zip/