安装PHP时，在第一步编译配置的时候出现以下信息。一时不得其解，最后看了一下信息内容，有一个错误日志文件debug.log。在错误日志文件里提到了error while loading shared libraries: libltdl.so.3: cannot open shared object file: No such file or director。就是系统缺少libltdl3的意思。
创新互联：从2013年开始为各行业开拓出企业自己的“网站建设”服务，为1000多家公司企业提供了专业的成都网站制作、成都做网站、外贸营销网站建设、网页设计和网站推广服务， 按需求定制网站由设计师亲自精心设计，设计的效果完全按照客户的要求，并适当的提出合理的建议，拥有的视觉效果，策划师分析客户的同行竞争对手，根据客户的实际情况给出合理的网站构架，制作客户同行业具有领先地位的。
于是在网上下载了https://rpmfind.net/linux/rpm2html/search.php?query=libltdl3&submit=Search+...&system=&arch=
libltdl3-1.5.18-1mdk.i586.rpm 安装成功后。重新编译安装PHP，成功。
提示：
1、libltdl.so.3 出现so的一般表示模块，而不是表示某个安装包。但可以根据模块的名称大致知道是什么软件包。
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