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

Commands by harpo from sorted by
Terminal - Commands by harpo - 11 results
nmap -sP
echo 1 > /proc/sys/sunrpc/nfs_debug
2014-08-12 14:40:55
User: harpo
Functions: echo

echo 1 > /proc/sys/sunrpc/nfs_debug && tail -f /var/log/messages

to debug NFS issues.

tcpdump host <IP> -nXXv -s0 -w file.pcap
dig +short -x <ip-address>
for i in /var/spool/cron/tabs/*; do echo ${i##*/}; sed 's/^/\t/' $i; echo; done
2012-07-12 08:07:20
User: harpo
Functions: echo sed

This is flatcaps tweaked command to make it work on SLES 11.2

for user in $(getent passwd|cut -f1 -d:); do echo "### Crontabs for $user ####"; crontab -u $user -l; done
2012-07-11 13:06:17
User: harpo
Functions: crontab cut echo getent
Tags: crontab getent

added echo "### Crontabs for $user ####"; to make clear whose crontab is listed.

for user in $(cut -f1 -d: /etc/passwd); do echo "### Crontabs for $user ####"; crontab -u $user -l; done
2012-07-11 12:25:56
User: harpo
Functions: crontab cut echo
Tags: crontab

added echo "### Crontabs for $user ####"; to make clear whose crontab is listed.

du -x / | sort -rn | less
2012-06-26 15:29:26
User: harpo
Functions: du sort
Tags: du

I had the problem that our monitoring showed that the "/" filesystem is >90% full. This command helped me to find out fast which subdirs are the biggest. The system has many NFS-mounts therefore the -x.

ls -ltr |grep 'May 12'|awk '{print $9;}'|xargs rm -v
dd if=/dev/zero of=filename.file bs=1024 count=10240
2012-01-19 08:38:14
User: harpo
Functions: dd

Command to create a dummy file (full of nulls). Useful for testing e.g. file transfers when no file is at hand.

bs = blocksize, count = filesize in kilobytes

for f in /*part1.rar;do unrar e .$f.;done