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On Sunday 18 April 2010 05:05:23 walt wrote: |
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> On 04/17/2010 06:02 PM, Jonathan wrote: |
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> > What does the E in EUID stand for? |
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> > I did a quick Google and found RUID and EUID but I did not find anything |
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> > else. |
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> |
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> Did you really type what you meant? Doesn't make much sense as is, so I |
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> assume there is a typo in there somewhere. |
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> |
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> Have a leisurely browse through /usr/include/unistd.h to answer your |
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> question. |
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Nice retort :-) |
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But to answer his question |
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The "E" stands for "effective". His apps are running as a normal user with his |
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UID. In kernel-speak they are effectively running with that UID, hence the |
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term EUID. |
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When you run an app with sudo (or any other app that raises priviledges), sudo |
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is SUID so it runs as root, who permits the user's app to run as root. The UID |
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of that running app is 0, but it's launched by a regular user. |
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That's why we have EUID. It's not the same thing as UID. |
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-- |
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alan dot mckinnon at gmail dot com |
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