sudo echo "something" >> /etc/privilegedFile doesn't work

bash shell scripting permissions sudo
David picture David · Sep 17, 2008 · Viewed 211.2k times · Source

This is a pretty simple question, at least it seems like it should be, about sudo permissions in Linux.

There are a lot of times when I just want to append something to /etc/hosts or a similar file but end up not being able to because both > and >> are not allowed, even with root.

Is there someway to make this work without having to su or sudo su into root?

Answer

Yoo picture Yoo · Feb 15, 2009

Use tee --append or tee -a.

echo 'deb blah ... blah' | sudo tee -a /etc/apt/sources.list

Make sure to avoid quotes inside quotes.

To avoid printing data back to the console, redirect the output to /dev/null.

echo 'deb blah ... blah' | sudo tee -a /etc/apt/sources.list > /dev/null

Remember about the (-a/--append) flag! Just tee works like > and will overwrite your file. tee -a works like >> and will write at the end of the file.

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