phpize No such file or directory 找不到头文件

$ phpize
grep: /usr/include/php/main/php.h: No such file or directory
grep: /usr/include/php/Zend/zend_modules.h: No such file or directory
grep: /usr/include/php/Zend/zend_extensions.h: No such file or directory
Configuring for:
PHP Api Version:        
Zend Module Api No:     
Zend Extension Api No:

缺少PHP的header头文件，再一看/usr/include文件夹根本不存在敲出如下命令：

$ xcode-select --install
xcode-select: note: install requested for command line developer tools

如果phpize还是无效、执行下列命令安装header头文件SDK即可：

$ cd /Library/Developer/CommandLineTools/Packages/
$ open macOS_SDK_headers_for_macOS_10.14.pkg