Cannot find autoconf. Please check your autoconf installation and the $PHP_AUTOCONF environment variable. Then, rerun this scrip

在运行phpize时出现的错误

> /data/php/bin/phpize

Configuring for:
PHP Api Version: 20131106
Zend Module Api No: 20131226
Zend Extension Api No: 220131226
Cannot find autoconf. Please check your autoconf installation and the
$PHP_AUTOCONF environment variable. Then, rerun this script.
问题的原因是没有安装autoconf，解决方法如下：

> yum install m4
> yum install autoconf