速度达到10M每秒，比APPSTORE强太多了，希望大家都用这个地址下载
Xcode 4.5.2
The is the release version of the complete Xcode developer toolset for Mac, iPhone, iPod touch, and iPad. It includes the iOS 6 SDK and OS X 10.8 SDK. Xcode 4.5.2 requires OS X Mountain Lion or OS X Lion.
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Command Line Tools (OS X Mountain Lion) for Xcode – November 2012
This package enables UNIX-style development via Terminal by installing command line developer tools, as well as Mac OS X SDK frameworks and headers. Many useful tools are included, such as the Apple LLVM compiler, linker, and Make. If you use Xcode, these tools are also embedded within the Xcode IDE, and can be installed on your system using the Downloads preferences pane within Xcode 4.5.
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Command Line Tools (OS X Lion) for Xcode – November 2012
This package enables UNIX-style development via Terminal by installing command line developer tools, as well as Mac OS X SDK frameworks and headers. Many useful tools are included, such as the Apple LLVM compiler, linker, and Make. If you use Xcode, these tools are also embedded within the Xcode IDE, and can be installed on your system using the Downloads preferences pane within Xcode 4.3 and later. This package requires Mac OS X 10.7.3 or later.
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