


Detailed 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
将输入进去后保存
#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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