Removing iOS SDKs from OSX

问题:

This isn't a programming question but it's about the SDKs and the IDE. I've accumulated a ton of different XCode installs over the past couple of years and now my hard drive is nearly full. With each SDK clocking in at around 5 gigs, and my storage space getting low, I have a couple of questions

3 Questions:

1. Can I remove old ones?
2. Where are they stored?
3. Does the newest SDK overwrite base classes from previous SDKs? (Does NSString.h now reside in two different SDKs or will the newest one take precedence?
4. What about beta 1, beta 2, beta 3 SDK versions? Does installing the GM/official eliminate the beta version from my Mac?
5. Most importantly, Can I still target 3.0 if I install the 4.2 SDK? (I understand the difference between base SDK and target SDK)

I want to clean my hard drive and I have about 18 GB remaining on a 160 GB drive. I'd like to just start over and reinstall OSX, download a fresh SDK, but I still have apps that are targeted to 3.1.2 and I don't want to be forced to only support 4.0.

Thank you

回答1:

Can I remove old ones?

Sure.

Where are they stored?

/Developer/Platforms/iPhone*/Developer/SDKs/ usually.

Does the newest SDK overwrite base classes from previous SDKs? (Does NSString.h now reside in two different SDKs or will the newest one take precedence?

No, you're fine to delete them. Each SDK is self contained.

What about beta 1, beta 2, beta 3 SDK versions? Does installing the GM/official eliminate the beta version from my Mac?

Sometimes, you can choose to reinstall them though

Most importantly, Can I still target 3.0 if I install the 4.2 SDK? (I understand the difference between base SDK and target SDK)

Yes

回答2:

As of May 2016:

Where are they stored?

• /Library/Developer/CoreSimulator/Profiles/Runtimes
• /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs
• /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/Library/CoreSimulator/Profiles/Runtimes

回答3:

You can choose to install Xcode in a different directory rather than have it overwrite your current version. See Can I have multiple Xcode versions installed? for details. Each installation stands on its own. Just be sure you know which one you're launching when opening your project.