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。

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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|                       *** ATTENTION ***                            |

|                                                                    |

| Something is likely to be messed up here, because the configure    |

| script was not able to detect a simple feature on your platform.   |

| This is often caused by incorrect configuration parameters. Please |

| see the file debug.log for error messages.                         |

|                                                                    |

| If you are unable to fix this, send the file debug.log to the      |

| php-install@lists.php.net mailing list and include appropiate      |

| information about your setup.                                      |

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| License:                                                           |

| This software is subject to the PHP License, available in this     |

| distribution in the file LICENSE.  By continuing this installation |

| process, you are bound by the terms of this license agreement.     |

| If you do not agree with the terms of this license, you must abort |

| the installation process at this point.                            |

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