1.下载memcache源代码文件

https://github.com/websupport-sk/pecl-memcache/archive/php7.zip

文件夹名为：pecl-memcache-php7

2.解压后进入文件夹执行如下命令

phpize

我执行phpize的遇到这个报错

$ 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 

 ./configure --with-php-config=/usr/local/opt/php\@7.1/bin/php-config

php-config修改为指定路径

which php-config

3.执行make & make install 命令

4、配置php.ini加入如下：

extension="memcache.so"

php.ini 路径
/private/etc/php.ini