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Hello, Alan. |
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On Fri, Feb 13, 2015 at 08:20:13PM +0200, Alan McKinnon wrote: |
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> On 13/02/2015 16:31, Alan Mackenzie wrote: |
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> > Hi, Gentoo. |
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> > I'm clearing out dross from my home directory, as me (not as root) and |
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> > I've just deleted this file: |
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> > -rw-r--r-- 1 root root 0 Apr 11 2011 grep |
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> > , simply by typing $ rm grep. I was prompted with: |
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> > rm: remove write-protected regular empty file ■grep■? |
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> > , to which I responded 'y'. The file is now gone. |
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> > So, as a non root user, I've managed to delete a file belonging to root, |
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> > to which I have no write access. This is crazy! I'm not happy about |
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> > this. What's going on? |
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> Nothing is going on, the system is working as designed and is doing it |
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> correctly. It's not the permissions of a file that apply to deletion, |
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> it's the permissions of the directory it's in. Because that's all a |
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> delete is - remove one linee from the directory index and the file goes |
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> away. |
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Ah. OK. That seems fairly straighforward to grasp. |
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> It's also the exact opposite of creating the file, how does that work? |
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> Well you can't have write permissions yet on a file that has not been |
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> created, the permissions must be the directory. Same with delete. |
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> Trust me, there is no arguing with this - Unix has always worked this |
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> way and likely always will. |
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:-) I ask myself, how come I've got this far without learning this |
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pretty basic fact? |
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Thanks for the explanation. |
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> -- |
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> Alan McKinnon |
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> alan.mckinnon@×××××.com |
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-- |
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Alan Mackenzie (Nuremberg, Germany). |
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