Compiling shared PECL extensions with phpize
Sometimes, using the pecl installer is not an option. This could be because you’re behind a firewall, or it could be because the extension you want to install is not available as a PECL compatible package, such as unreleased extensions from SVN. If you need to build such an extension, you can use the lower-level build tools to perform the build manually.
The phpize command is used to prepare the build environment for a PHP extension. In the following sample, the sources for an extension are in a directory named extname:
$ cd extname 进入到源码包中的扩展目录
$ phpize 运行phpize。路径不一定在当前目录下，去寻找phpize运行。之后会生成了一个configure文件
$ ./configure 运行。 如果生成基于数据库的扩展，需要加上参数运行：1,–with-php-config。2,”–with-具体的数据库参数”.比如, –with-pgsql、–with-mysql
$ make
# make install 将会生成一个extname.so的扩展，被放到了PHP extensions directory
A successful install will have created extname.so and put it into the PHP extensions directory. You’ll need to and adjust php.ini and add an extension=extname.so line before you can use the extension.
If the system is missing the phpize command, and precompiled packages (like RPM’s) are used, be sure to also install the appropriate devel version of the PHP package as they often include the phpize command along with the appropriate header files to build PHP and its extensions.
Execute phpize –help to display additional usage information.
phpize的作用可以这样理解：侦测环境(phpize工具是在php安装目录下，所以是要根据该php的配置情况生成对应的configure文件)，建立一个configure文件。必须在一个目录下去运行phpize。那么phpize就知道你的的环境是哪个目录，并且configure文件建立在该目录下。
步骤总结：
一、cd /usr/src/php源码包目录/ext/扩展目录/
二、/usr/local/php5314/bin/phpize
三、./configure –with-php-config=/usr/local/php5314/bin/php-config
注：xampp安装的话默认用 ./configure –with-php-config=/opt/lampp/bin/php-config
四、make && make install
五、剩下是配置php.ini
假如你的服务器上安装了多个版本php，那么需要告诉phpize要建立基于哪个版本的扩展。通过使用–with-php-config=指定你使用哪个php版本。
比如：–with-php-config=/usr/local/php524/bin/php-config
关于php-config文件：是在php编译生成后(安装好)，放在安装目录下的一个文件。
疑问：phpize是在php安装目录下的一个文件。比如我安装了两个php5.2 和php5.3那么使用phpize也要使用对应版本的phpize才行吧，此时使用–with-php-config有什么作用？
phpize工具一般在哪里？
当php编译完成后，php安装目录下的bin目录下会有phpize这个脚本文件。所以是去安装好的php安装目录先去找。