安装PHP经常会出现少库文件，下面是总结的一些常遇到的：
1、configure: error: xml2-config not found. Please check your libxml2 installation.
yum -y install libxml2-devel
2、checking for cURL in default path… not found
configure: error: Please reinstall the libcurl distribution –
easy.h should be in /include/curl/
yum -y install curl-devel
3、configure: error: jpeglib.h not found.
yum -y install libjpeg-devel
4、error: png.h not found.
yum -y install libpng-devel
5、configure: error: freetype-config not found.
yum -y install freetype-devel
6、configure: error: mcrypt.h not found. Please reinstall libmcrypt
rpm -ivh "http://www.lishiming.net/data/attachment/forum/month_1211/epel-release-6-7.noarch.rpm"
yum install -y libmcrypt-devel
因为centos6.x 默认的yum源没有libmcrypt-devel 这个包，只能借助第三方yum源。
7、configure: error: Please reinstall the BZip2 distribution
yum install -y bzip2-devel