How do I use sudo to redirect output to a location I don’t have permission to write to? [closed]

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I’ve been given sudo access on one of our development RedHat linux boxes, and I seem to find myself quite often needing to redirect output to a location I don’t normally have write access to.

The trouble is, this contrived example doesn’t work:

sudo ls -hal /root/ > /root/test.out

I just receive the response:

-bash: /root/test.out: Permission denied

How can I get this to work?

15 s
15

Your command does not work because the redirection is performed by your shell which does not have the permission to write to /root/test.out. The redirection of the output is not performed by sudo.

There are multiple solutions:

  • Run a shell with sudo and give the command to it by using the -c option:

    sudo sh -c 'ls -hal /root/ > /root/test.out'

  • Create a script with your commands and run that script with sudo:

    #!/bin/sh
ls -hal /root/ > /root/test.out

    Run sudo ls.sh. See Steve Bennett’s answer if you don’t want to create a temporary file.

  • Launch a shell with sudo -s then run your commands:

    [nobody@so]$ sudo -s
[root@so]# ls -hal /root/ > /root/test.out
[root@so]# ^D
[nobody@so]$

  • Use sudo tee (if you have to escape a lot when using the -c option):

    sudo ls -hal /root/ | sudo tee /root/test.out > /dev/null

    The redirect to /dev/null is needed to stop tee from outputting to the screen. To append instead of overwriting the output file
    (>>), use tee -a or tee --append (the last one is specific to GNU coreutils).

Thanks go to Jd, Adam J. Forster and Johnathan for the second, third and fourth solutions.

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