PHP get ifconfig eth0 down permission solution via sudo

PHP gets ifconfig eth0 down permissions via sudo
I have already opened a lot of posts, I really can not achieve the hope that the great God to guide anything, even if it is the information of PHP sudo access to the right online is really not reliable AH

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I am: sudo gedit/etc/sudoers modified without sudo to lose the password
Http://jingyan.baidu.com/article/495ba84135a16738b30eded1.html
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The answer is

1. Create a file, such as Pw.txt, to save your root password. For example, a password of 1234
Remember, the contents of the file are only 1234

2.php File Contents
Shell_exec (' sudo-u root-s ifconfig eth0 down <./pw.txt ');

Test Shutdown network card gracefully
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As you pointers, the user protection of the operating system is not a fake?

Put the action you need into the shell file, either in the waiting process or in a scheduled task
Only forward first check if there is a start signal, if not do not execute
Start signal can be a file, can be written in PHP web-style

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