What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Universal configuration monitoring and system of record for IT.

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:



May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

List all groups and the user names that were in each group

Terminal - List all groups and the user names that were in each group
for u in `cut -f1 -d: /etc/passwd`; do echo -n $u:; groups $u; done | sort
2009-08-22 09:06:02
User: hemanth
Functions: echo groups
List all groups and the user names that were in each group

"cut" the user names from /etc/passwd and then running a loop over them.


There are 7 alternatives - vote for the best!

Terminal - Alternatives
groups $(cut -f1 -d":" /etc/passwd) | sort

Know a better way?

If you can do better, submit your command here.

What others think

Glad you're enjoying our blog. In future, however, it would be nice if you gave some attribution when you're posting our content here on commandlinefu. This one is from http://blog.commandlinekungfu.com/2009/06/episode-44-users-groups-part-ii.html

By the way, this command lists all groups that each user is a member of, not the users in each group. For the latter answer, see http://blog.commandlinekungfu.com/2009/06/episode-43-users-groups.html

Comment by Hal_Pomeranz 405 weeks ago

it's shorter in my fedora:

for u in `cut -f1 -d: /etc/passwd`; do groups $u; done | sort

Comment by Charon 404 weeks and 5 days ago

Your point of view

You must be signed in to comment.