用mac 自带的终端执行的命令，安装安装Vapor和toolbox
安装指令:
macdeMacBook-Pro:~ mac$ curl -sL check.vapor.sh| bash
结果报这个错误：
xcode-select: error: tool ‘xcodebuild‘ requires Xcode, but active developer directory ‘/Library/Developer/CommandLineTools‘ is a command line tools instance ?? We don‘t recognize your Command Line Tools version. Open Xcode and make sure the correct SDK is selected: ?? Xcode > Preferences > Locations > Command Line Tools Expected: Xcode 8 or 9 (Any Build Number) Current: ?? Visit our docs for step-by-step instructions on installing Swift correctly. http://docs.vapor.codes ?? or Join our Slack and we‘ll help you get setup. http://vapor.team
看到这里发现是提示路径不对
Open Xcode and make sure the correct SDK is selected: ?? Xcode > Preferences > Locations > Command Line Tools
用这个命令切换到你正在用的Xcode安装路径下（需要输入Mac密码）
macdeMacBook-Pro:~ mac$ sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer/ Password:
macdeMacBook-Pro:~ mac$ curl -sL check.vapor.sh| bash ? Xcode 9 is compatible with Vapor 2. ? Xcode 9 is compatible with Vapor 3. ? Swift 4.1 is compatible with Vapor 2. ? Swift 4.1 is compatible with Vapor 3.
结果成功了！
为什么会出现这种错误呢，原来是我安装了2个Xcode。所以，安装了多个Xcode的时候，就要注意
Xcode - xcode-select: error: tool 'xcodebuild' requires Xcode报错解决方案
原文：https://www.cnblogs.com/gongyuhonglou/p/8963396.html