MAC OS X 10.9.5系统里已经自带了 apache 和 php ，只是默认没有启用，我们将他们启用即可。
APACHE的默认版本是 Apache/2.2.26 (Unix)，php版本是PHP 5.4.30。
由于调试程序需要，我需要同时安装低版本的php5.3，但是又不希望删除系统预装的php 5.4，或升级/降级系统的php5.4，那么怎么办呢？这个时候，就可以通过brew的方式安装新的php版本。
第一步，先安装 brew
Brew 是 Mac 下面的包管理工具，通过 Github 托管适合 Mac 的编译配置以及 Patch，可以方便的安装开发工具。 Mac 自带ruby 所以安装起来很方便，同时它也会自动把git也给你装上。官方网站： http://brew.sh
在mac下终端里直接输入命令行：
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
安装完成之后，建议执行一下自检：brew doctor 如果看到Your system is ready to brew. 那么你的brew已经可以开始使用了。
常用命令： （所有软件以PHP5.5为例子）
brew update #更新brew可安装包，建议每次执行一下
brew search php55 #搜索php5.5
brew tap josegonzalez/php #安装扩展<gihhub_user/repo>
brew tap #查看安装的扩展列表
brew install php55 #安装php5.5
brew remove php55 #卸载php5.5
brew upgrade php55 #升级php5.5
brew options php55 #查看php5.5安装选项
brew info php55 #查看php5.5相关信息
brew home php55 #访问php5.5官方网站
brew services list #查看系统通过 brew 安装的服务
brew services cleanup #清除已卸载无用的启动配置文件
brew services restart php55 #重启php-fpm
第二步，安装PHP
先添加brew的PHP扩展库：
brew update
brew tap homebrew/dupes
brew tap homebrew/php
brew tap josegonzalez/homebrew-php
可以使用 brew options php53 命令来查看安装php5.3的选项，这里我用下面的选项安装：
brew install php53 --with-apache --with-gmp --with-imap --with-tidy --with-debug
请注意：如果你希望以mac下的apache作为web server，编译时要加 --with-apache；如果你的web server 是 nginx这类，就需要加上 --with-fpm。
Options
--disable-opcache
Build without Opcache extension
--disable-zend-multibyte
Disable auto-detection of Unicode encoded scripts
--homebrew-apxs
Build against apxs in Homebrew prefix
--with-apache
Enable building of shared Apache 2.0 Handler module, overriding any options which disable apache
--with-cgi
Enable building of the CGI executable (implies --without-apache)
--with-debug
Compile with debugging symbols
--with-fpm
Enable building of the fpm SAPI executable (implies --without-apache)
--with-gmp
Build with gmp support
--with-homebrew-curl
Include Curl support via Homebrew
--with-homebrew-libxslt
Include LibXSLT support via Homebrew
--with-homebrew-openssl
Include OpenSSL support via Homebrew
--with-imap
Include IMAP extension
--with-libmysql
Include (old-style) libmysql support instead of mysqlnd
--with-mssql
Include MSSQL-DB support
--with-pdo-oci
Include Oracle databases (requries ORACLE_HOME be set)
--with-phpdbg
Enable building of the phpdbg SAPI executable (PHP 5.4 and above)
--with-postgresql
Build with postgresql support
--with-thread-safety
Build with thread safety
--with-tidy
Include Tidy support
--without-bz2
Build without bz2 support
--without-mysql
Remove MySQL/MariaDB support
--without-pcntl
Build without Process Control support
--without-pear
Build without PEAR
--without-snmp
Build without SNmp support
--HEAD
Install HEAD version
PHP编译过程中如果遇到 configure: error: Cannot find OpenSSL's <evp.h> 错误，执行 xcode-select --install 重新安装一下 Xcode Command Line Tools 即可解决该错误（来源：https://github.com/Homebrew/homebrew-php/issues/1181）。
安装完php后，会有一段提示，请仔细阅读：
Caveats
To enable PHP in Apache add the following to httpd.conf and restart Apache:
LoadModule php5_module /usr/local/opt/php53/libexec/apache2/libphp5.so
The php.ini file can be found in:
/usr/local/etc/php/5.3/php.ini
PEAR
If PEAR complains about permissions, 'fix' the default PEAR permissions and config:
chmod -R ug+w /usr/local/Cellar/php53/5.3.29/lib/php
pear config-set php_ini /usr/local/etc/php/5.3/php.ini
Extensions
If you are having issues with custom extension compiling, ensure that
you are using the brew version, by placing /usr/local/bin before /usr/sbin in your PATH:
PATH="/usr/local/bin:$PATH"
PHP53 Extensions will always be compiled against this PHP. Please install them
using --without-homebrew-php to enable compiling against system PHP.
PHP CLI
If you wish to swap the PHP you use on the command line, you should add the following to ~/.bashrc,
~/.zshrc, ~/.profile or your shell's equivalent configuration file:
export PATH="$(brew --prefix homebrew/php/php53)/bin:$PATH"
To have launchd start php53 at login:
ln -sfv /usr/local/opt/php53/*.plist ~/Library/LaunchAgents
Then to load php53 now:
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.php53.plist
==> Summary
/usr/local/Cellar/php53/5.3.29: 480 files, 31M, built in 12.9 minutes
等待PHP编译完成，开始安装PHP常用扩展，扩展安装过程中 brew会自动安装依赖包，使用 brew search php53- 命令，可以查看还有哪些扩展可以安装，然后执行 brew install php53-XXX 就可以了。
由于Mac自带了php和php-fpm，因此需要添加系统环境变量PATH来替代自带PHP版本：
echo 'export PATH="$(brew --prefix homebrew/php/php53)/bin:$PATH"' >> ~/.bash_profile #for php
echo 'export PATH="$(brew --prefix homebrew/php/php53)/sbin:$PATH"' >> ~/.bash_profile #for php-fpm
echo 'export PATH="/usr/local/bin:/usr/local/sbin:$PATH"' >> ~/.bash_profile #for other brew install soft
source ~/.bash_profile #更新配置
如何卸载安装的 php5.3呢？
# 卸载
brew uninstall php53
# 清除缓存以及老旧版本文件
brew cleanup -s
测试一下效果：
$ php -v
PHP 5.3.29 (cli) (built: Jan 24 2015 12:40:58) (DEBUG)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2014 Zend Technologies
# mac系统自带的php
$ /usr/bin/php -v
PHP 5.4.30 (cli) (built: Jul 29 2014 23:43:29)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies
with Zend Guard Loader v3.3, Copyright (c) 1998-2013, by Zend Technologies
由于我们没有安装php的fpm模式，所以 php-fpm -v 命令显示的是mac自带的：
$ php-fpm -v
PHP 5.4.30 (fpm-fcgi) (built: Jul 29 2014 23:44:15)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies
with Zend Guard Loader v3.3, Copyright (c) 1998-2013, by Zend Technologies
这个时候，我们使用 phpinfo 函数显示出来的php版本还是max自带的PHP5.4，需要我们修改 apache的配置文件 httpd.conf，加载的php5模块路径指向刚刚安装的 php5.3目录里的 libphp5.so：
LoadModule php5_module /usr/local/opt/php53/libexec/apache2/libphp5.so
重启apache，phpinfo() 脚本里显示的 php 版本就变成了 PHP Version 5.3.29。