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HomeBackend DevelopmentPHP TutorialDetailed explanation of how to use md5 function to encrypt strings in PHP under Linux

利用PHP脚本在Linux下用md5函数加密字符串的方法,只需Linux系统中安装过PHP然后在命令行中操作文中示例即可

#touch  a.php  //创建a.php文件

#vi a.php  //用vi 编辑a.php文件

输入进去后保存

#php  a.php  //运行a.php文件

显示:e10adc3949ba59abbe56e057f20f883e

A.在linux或Unix上,md5sum是用来计算和校验文件报文摘要的工具程序。一般来说,安装了Linux后,就会有md5sum这个工具,直接在命令行终端直接运行。可以用下面的命令来获取md5sum命令帮助 man md5sum

#md5sum –help

有个提示:“With no FILE, or when FILE is -, read standard input.”翻译过来就是“如果没有输入文件选项或者文件选项为 -   ,则从标砖读取输入内容”,即可以直接从键盘读取字符串来加密。

利用md5sum加密字符串的方法

# md5sum     //然后回车

123456      //输入123456.然后按两次ctrl+d.

显示:

 代码如下:

123456e10adc3949ba59abbe56e057f20f883e

     红色代表加密后的值

还可以用管道命令:

代码如下:

#echo   -n '123123' | md5sum

或者写成md5加密脚本,名字叫md5.sh,

将以下内容复制进脚本里:

 代码如下:

#!/bin/bash
echo   -n   $1 | md5sum | awk '{print $1}'

保存后,给脚本执行权限。

代码如下:

#sh  md5.sh   123456

显示:e10adc3949ba59abbe56e057f20f883e

B.其实也可以将文本放入文本文件,然后用md5sum 加密改文本,也可以得到字符串加密的值。过程如下:

代码如下:

#touch a.txt
#echo  -n   123456 > a.txt    //将123456写进文本文件,不能丢了 –n参数,避免回车符干扰
#md5sum    a.txt

显示:e10adc3949ba59abbe56e057f20f883e     a.txt

ctrl+d有两个含义:

一是向程序发送文件输入结束符EOF。

二是向程序发送exit退出指令。程序收到信号后具体动作是结束输入、然后等待,还是直接退出,那就要看该程序捕获信号后是如何操作的了。
md5sum属于第一个含义。两次strl+d了,第一次读取EOF指令,再次捕获就会当成exit指令。而shell一类的程序,会直接把ctrl+d解析为退出指令。

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