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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!

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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

All commands from sorted by
Terminal - All commands - 12,362 results
ssh -MNf <user>@<host>
2009-02-26 14:11:19
User: raphink
Functions: ssh

Create a persistent SSH connection to the host in the background. Combine this with settings in your ~/.ssh/config:

Host host

ControlPath ~/.ssh/master-%r@%h:%p

ControlMaster no

All the SSH connections to the machine will then go through the persisten SSH socket. This is very useful if you are using SSH to synchronize files (using rsync/sftp/cvs/svn) on a regular basis because it won't create a new socket each time to open an ssh connection.

mount /path/to/file.iso /mnt/cdrom -oloop
2009-02-05 17:28:06
User: nerd65536
Functions: mount
Tags: mount iso

"-o loop" lets you use a file as a block device

ssh-keygen -R <the_offending_host>
2010-07-11 19:37:24
User: bunam
Functions: ssh ssh-keygen
Tags: sed

In this case it's better do to use the dedicated tool

chmod --reference file1 file2
2010-03-31 12:05:48
User: rpavlick
Functions: chmod
Tags: chmod chown chgrp

Also works with:

chgrp --reference file1 file2 chown --reference file1 file2
ssh -t remote_host screen -r
2009-07-23 06:15:04
User: recursiverse
Functions: screen ssh
Tags: ssh screen

Directly attach a remote screen session (saves a useless parent bash process)

ps awwfux | less -S
2009-07-04 09:39:28
User: ToyKeeper
Functions: less ps

If you want a visual representation of the parent/child relationships between processes, this is one easy way to do it. It's useful in debugging collections of shell scripts, because it provides something like a call traceback.

When a shell script breaks, just remember "awwfux".

find . -type d -empty -delete
bind -P
2012-05-28 18:51:59
User: ricardofunke

This command shows the various shortcuts that can be use in bash, including Ctrl+L, Ctrl+R, etc...

You can translate "\C-y" to Ctrl+y, for example.

sed -n 5p <file>
2009-10-15 11:00:48
User: Waldirio
Functions: sed

You can get one specific line during any procedure. Very interesting to be used when you know what line you want.

ssh -t hostA ssh hostB
2009-08-27 21:35:19
User: 0x89
Functions: ssh

Of course you need to be able to access host A for this ;-)

% screen -r someuser/
2009-03-25 23:59:38
User: totoro
Functions: screen

If you enable multiuser, then you can permit others to share your screen session. The following conditions apply:

1. screen must be suid root;

2. "multiuser on" must be configured in ~/.screenrc;

3. control the others user(s) access with "aclchg":

# ----- from ~/.screenrc-users -----

aclchg someuser +rx "#?" #enable r/o access to "someuser"

aclchg someuser -x "#,at,aclchg,acladd,acldel,quit" # don't allow these

aclchg otheruser +rwx "#?" # enable r/w access to "otheruser"

aclchg otheruser -x "#,at,aclchg,acladd,acldel,quit" # don't allow them to use these commands

# -----

After doing this (once), you start your session with:

$ screen

Then, the other user can join your terminal session(s) with youruserid:

$ screen -r youruserid/

Note: the trailing "/" is required.

Multiple users can share the same screen simultaneously, each with independent access controlled precisely with "aclchg" in the ~/.screenrc file.

I use the following setup:

# ~/.screenrc-base

# default screenrc on any host

source $HOME/.screenrc-base

source $HOME/.screenrc-$HOST

source $HOME/.screenrc-users

# -----

Then, the base configurations are in ~/.screenrc-base; the host-specific configurations are in ~/.screenrc-$HOST, and the user configurations are in ~/.screenrc-users.

The host-specific .screenrc file might contain some host-specific screen commands; e.g.:

# ~/.screen-myhost

# -----

screen -t 'anywhere' /bin/tcsh

screen -t 'anywhere1' /bin/tcsh

# ----

The .screenrc-base contains:

# ~/.screenrc-base

## I find typing ^a (Control-a) awkward. So I set the escape key to CTRL-j instead of a.

escape ^Jj

termcapinfo xterm* ti@:te@:

autodetach on

zombie kr

verbose on

multiuser on

echo "rm -rf /unwanted-but-large/folder" | batch
2009-02-04 19:07:52
User: root
Functions: echo

Good for one off jobs that you want to run at a quiet time. The default threshold is a load average of 0.8 but this can be set using atrun.

timeout 5s COMMAND
rtfm() { help $@ || man $@ || $BROWSER "http://www.google.com/search?q=$@"; }
cat /dev/urandom | hexdump -C | grep "ca fe"
2010-09-27 08:20:44
Functions: cat grep hexdump

just make some data scrolling off the terminal. wow.

tar -tf <file.tar.gz> | xargs rm -r
script -qf | tee >(nc -kl 5000) >(nc -kl 5001) >(nc -kl 5002)
2010-10-11 07:55:30
User: clvv
Functions: script tee
Tags: tee pipe script nc

run 'nc yourip 5000', 'nc yourip 5001' or 'nc yourip 5002' elsewhere will produce an exact same mirror of your shell. This is handy when you want to show someone else some amazing stuff in your shell without giving them control over it.

google docs edit --title "To-Do List" --editor vim
2010-06-21 16:15:42
User: spiffwalker
Tags: google

Google just released a new commend line tool offering all sorts of new services from the commend line. One of them is uploading a youtube video but there are plenty more google services to interact with.

Download it here: http://code.google.com/p/googlecl/

Manual: http://code.google.com/p/googlecl/wiki/Manual

This specific command courtesy of lifehacker:http://lifehacker.com/5568817/

Though all can be found in manual page linked above.

diff <(lsof -p 1234) <(sleep 10; lsof -p 1234)
2010-03-15 22:55:32
User: zlemini
Functions: diff sleep

This command takes a snapshot of the open files for a PID 1234 then waits 10 seconds and takes another snapshot of the same PID, it then displays the difference between each snapshot to give you an insight into what the application is doing.

sudo touch /forcefsck
2009-10-29 17:04:47
User: johnraff
Functions: sudo touch

The empty file /forcefsck causes the file system check fsck to be run next time you boot up, after which it will be removed.

This works too:

sudo >/forcefsck
ls -d */
2009-10-08 22:07:22
User: brianmuckian
Functions: ls

-d: list directory entries instead of contents, and do not dereference symbolic links

cp file.txt{,.bak}
2009-01-26 12:11:29
User: root
Functions: cp

Uses shell expansion to create a back-up called file.txt.bak

until !!; do :; done
date --set="$(ssh [email protected] date)"
2011-08-30 20:03:06
User: splante
Functions: date
Tags: ssh ,NTP ,Date

Shorter, easier to remember version of cmd#7636

NTP is better, but there are situations where it can't be used. In those cases, you can do this to sync the local time to a server.

wget -q -U Mozilla -O output.mp3 "http://translate.google.com/translate_tts?ie=UTF-8&tl=en&q=hello+world
2011-03-08 14:05:36
User: sairon
Functions: wget

EDIT: command updated to support accented characters!

Works in any of 58 google supported languages (some sound like crap, english is the best IMO).

You get a mp3 file containing your query in spoken language. There is a limit of 100 characters for the "q" parameter, so be careful. The "tl" parameter contains target language.