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Holly Bostick wrote: |
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> JimD schreef: |
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>> I have been using Linux for a number of years and the one "trick" I |
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>> have never read how to do is something like: |
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>> |
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>> sudo echo "app-portage/porthole ~*" >> /etc/portage/package.keywords |
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> |
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> Well this one I do with a set of revised command nicked from the list, |
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> entered into ~/.bashrc, and requiring that |
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> |
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> 1) "su" is one of the commands that you are allowed to execute via sudo |
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> |
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> 2) you are exempted from needing to enter a password for 'sudo su': |
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> |
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> addkey(){ |
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> sudo su -c "echo $* >> /etc/portage/package.keywords" |
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> } |
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What's the use of su here? I don't understand. |
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What's happening is, that a root process executes |
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su -c "echo $* >> /etc/portage/package.keywords" |
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But why switch user from root to root to execute |
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echo $* >> /etc/portage/package.keywords |
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I don't understand that. Please explain. |
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> The general idea being that a) sudo seems to be a bit weird; even though |
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> it allows you to perform operations as if you are root, it doesn't do so |
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> by pretending that you _are_ root, |
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Uh? What are you talking about? The command is run with root |
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rights. If you use "sudo -H", even $HOME is set to ~root. |
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> so you still couldn't write to the |
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> /etc/portage/package.* files; |
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Yes, you can. The error is, that with |
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sudo echo blah >> file |
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Here the NORMAL USER does ">> file", *NOT* the root |
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echo process! |
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Have a read in your shell manpage. |
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> b) su does pretend you are root, |
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What do you mean with that? |
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>> Another one I always wanted to know if it is possible is: |
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>> |
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>> sudo > /var/log/foo.log |
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> |
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> I'm sure it is, with a bit of creativity, though I honestly don't know |
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> what your intention is in any case, since this looks to me like you're |
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> logging the output of the sudo command to foo.log (but since there is no |
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> output really to typing 'sudo', I have no idea what result you might |
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> expect). |
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A truncated file is to be expected, as that's what's happening |
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when you do |
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> filename |
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> Anyway, hope this is to some degree helpful; what you most likely want |
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> to do is read up on bash scripting to understand how to chain the |
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> commands that do what you want to get done with sudo. |
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Yep. |
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Alexander Skwar |
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-- |
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Keep brain from freezing. |
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|
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-- Homer Simpson |
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Simpson and Delilah |
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-- |
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