Adding a new user to all groups where another user is

You just added a user to your UNIX system. You want him to belong to all groups where you belong. E.g.: let's say your user name is bronto and the new user is robin. Here we go.

perl -F: -i.save -ape 'if ($F[3] =~ m{bronto} and not m{robin}) { chom
+p ; $_ .= qq{,robin\n} }' /etc/group
[download]

Comment on Adding a new user to all groups where another user is Download Code

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Re: Adding a new user to all groups where another user is by Limbic~Region (Chancellor) on May 12, 2008 at 17:59 UTC
bronto, `perl -F: -i.save -ape 'if ($F[3] =~ m{bronto} and not m{robin}) { chom +p ; $_ .= qq{,robin\n} }' /etc/group` [download] The first thing I see wrong with this is that you ignore the possibility that one user name may be contained within another. For instance - jon and jonathan. The second thing I see wrong is that you don't consider that a user's primary group need not be specified in /etc/group if it is present in /etc/passwd. For instance - bronto may belong to group 123 but not appear in group 123's line in /etc/group. At least on some *nix - which would mean 'robin' didn't end up in all groups as 'bronto'. The last thing is, your documentation is lacking. I know what -i.save does but would everyone who used it? What if someone made a typo - would they know how to undo it? Cheers - L~R	[reply] [d/l]
Just a memo and a hint... [Re^2: Adding a new user to all groups where another user is] by bronto (Priest) on May 17, 2008 at 12:56 UTC
Hi! Yep, every single byte you wrote is plain right. Thanks for taking the time to read and comment this node. I sometimes need to solve problems, like the one above, that require me a one-liner solution. When it happens, I often save the one liner in a file for future use, along with a very short comment to remind me what I wrote it for. I Often won't use it again as-is, but at least I have a good starting point for the next time. Basically, I did the same thing, publishing this one here instead of just saving it locally. So... have fun! `:-)` Ciao! `--bronto` In theory, there is no difference between theory and practice. In practice, there is.	[reply]


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