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Showing posts from April, 2016

How to use sudo and output redirection

It often happens that you need to echo or cat something to some config file, or maybe a log, or something else owned by root. It also often happens that you try to run it as a regular user and get a permission denied error. And normally you'd just prepend your command with sudo and be done with it, but output redirects are not that easy: current shell will handle them itself, they will not be passed to sudo and you will still have your permission problem. Luckily, the fix is easy: instead of prepending the command, you just replace > somefile with | sudo tee somefile and >> somefile with | sudo tee -a somefile  whatever the command before was. You may also add > /dev/null if you don't want if to echo everything. Example: echo "truncated" | sudo tee /var/log/toolong.log echo "additional log record" | sudo tee -a /var/log/toolong.log Of course, this is not the only way and it's not always the best but it works all the time, it