How to remove old versions of iPhone SDK when installing the new one?

I have downloaded iPhone SDK 4.0.2, I wanted to install it, but it looks that I don't have enough space. This made me think that maybe I could unistall the previous versions of iPhone SDK and install only the newest one.

Does anyone know how to do this? Should I keep the old versions? Is there any s开发者_JAVA百科ituation they could be useful?

Thanks for sharing your thoughts!

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Should you remove old versions? Up to you. You'll certainly have a "clean" installation. Do whatever you think is best for you. (You might want to reboot your system after uninstalling.)

Paul Peelen linked the command line step to do the removal, but I'm going to quote ad verbatim from Apple's "About Xcode.pdf" since the link could disappear:

Uninstalling Xcode Developer Tools

To uninstall Xcode developer tools on the boot volume along with the directory, from a Terminal window type:

$ sudo <Xcode>/Library/uninstall-devtools -mode=all

To remove the underlying developer content on the boot volume, but leave the directory and supporting files untouched, from a Terminal window type:

$ sudo <Xcode>/Library/uninstall-devtools --mode=systemsupport

To just remove the UNIX development support on the boot volume, but leave the directory and supporting files untouched, from a Terminal window type:

$ sudo <Xcode>/Library/uninstall-devtools --mode=unixdev

Finally, to just uninstall the directory you can simply drag it to the trash, or from a Terminal window type:

$ sudo <Xcode>/Library/uninstall-devtools --mode=xcodedir

NOTE: The uninstaller that ships with previous versions of the Xcode developer tools will not clean everything off of your system properly. You should use the one installed with these Xcode developer tools.

(Those are current at least as of "Xcode 3.2.3 for Mac OS X 10.6 and iPhone OS 4.0")

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You can use appzapper, or just remove the stuff in /Developer/Applications (I believe).

Edit: Asked my friend google, and this is what it came up with: http://macdevelopertips.com/xcode/how-to-uninstall-xcode.html

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The new iOS SDK overwrites most of the old one (unless you change the installation directory), so it doesn't really double the disk space usage.