问题表现：
在centos 7编译安装apache 2.2后，启动时遇到如下问题：
[root@bj-zw-boss-tomcat-v-0-21 local]# /usr/local/apache2.2.4/bin/apachectl -k start
/usr/local/apache2.2.4/bin/httpd: error while loading shared libraries: libexpat.so.0: cannot open shared object file: No such file or directory
问题分析解决办法：
缺少libexpat.so.0模块，可以通过软连接创建一个：
[root@bj-zw-boss-tomcat-v-0-21 local]# ln -sv /usr/lib64/libexpat.so.1 /usr/lib64/libexpat.so.0
‘/usr/lib64/libexpat.so.0’ -> ‘/usr/lib64/libexpat.so.1’
再次启动：
[root@bj-zw-boss-tomcat-v-0-21 local]# /usr/local/apache2.2.4/bin/apachectl -k start
验证Apache启动成功：
