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Find duplicate UID in /etc/passwd

Terminal - Find duplicate UID in /etc/passwd
awk -F":" '!list[$3]++{print $3}' /etc/passwd
2012-01-24 12:47:52
User: richard
Functions: awk
4
Find duplicate UID in /etc/passwd

You can use only awk

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
awk -F: '{print $3}' /etc/passwd | sort |uniq -d
2012-01-17 11:16:35
User: ultips
Functions: awk sort uniq
0

Detect duplicate UID in you /etc/passwd (or GID in /etc/group file).

Duplicate UID is often forbidden for it can be a security breach.

Know a better way?

If you can do better, submit your command here.

What others think

Your command print all the UIDs, you have to remove the "!" before "list" if you want to print only the duplicated one.

Comment by ultips 188 weeks and 2 days ago

Example prints out a list of UIDs that appear, and outputs each UID only once... so it doesn't find duplicates.

Comment by Mozai 187 weeks and 1 day ago

Your point of view

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