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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 - 12,392 results
sftp -s "sudo /usr/lib/sftp-server" [email protected]
2009-03-29 07:02:58
User: mrtheplague
Functions: sftp

This requires that your sudo not prompt for a password, as sftp cannot allocate the terminal necessary to ask.

watch --no-title -d -n 1 'echo `date -d "next Thursday" +%s` "-" `date +%s` | bc -l'
2009-03-29 06:53:09
User: jnash
Functions: bc watch

Might be more useful if you were able to print it in Days HH:MM:SS format as:

perl -e [email protected]=gmtime(234234);printf("%d Days %02d:%02d:%02ds\n",@p[7,2,1,0]);'

But I'm not exactly sure how to replace the 234234 with the output of the countdown time. (Having some problems with nested quoting/command substitution). Help would be appreciated :)

dscacheutil -flushcache
< /path/to/file.txt grep foo
2009-03-29 02:43:40
User: atoponce
Functions: grep

Several times, I find myself hitting my up arrow, and changing the search term. Unfortunately, I find myself wasting too much time typing:

grep kernel /var/log/messages

Redirecting STDIN allows me to put the search term at the end so I less cursor movement to change what I'm searching for:

< /var/log/messages grep kernel

If you're using the emacs keyboard binding, then after you press your up arrow, press CTRL+w to erase the word.

If this has already been submitted, I couldn't find it with the search utility.

rpm -q kernel-2* | grep -v $(uname -r) | xargs yum erase -y
2009-03-28 21:41:15
User: Nick
Functions: grep rpm uname xargs

On Fedora clean the boot directory; erase older kernel

netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
2009-03-28 21:02:26
User: tiagofischer
Functions: awk cut netstat sort uniq

Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount.

BSD Version:

netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr
dpkg --get-selections > LIST_FILE
2009-03-28 17:45:29
User: cammarin

This command is useful when you want to install the same packages on another fresh OS install for example. To do that, use:

sudo dpkg --set-selections < LIST_FILE
urpmi --auto-update --force # apply all pending updates (Mandriva Linux)
2009-03-28 14:59:26
User: mpb

Update a Mandriva Linux system with any pending updates.

This command needs to be run with root privilege.

Using the "--force" option answers "yes" to any interactive prompts

thus allowing the updates to be left unattended to completion.

NB if there is an update for glibc and/or a new kernel then the system

would need to be rebooted for these to take effect.

A prerequisite for running "urpmi --auto-update" is to have correctly defined

urpmi media sources (which can be done by visiting http://easyurpmi.zarb.org/).

If there are no new updates the the message "Packages are up to date" is shown.

awk '/start_pattern/,/stop_pattern/' file.txt
2009-03-28 14:28:59
User: atoponce
Functions: awk

I find this terribly useful for grepping through a file, looking for just a block of text. There's "grep -A # pattern file.txt" to see a specific number of lines following your pattern, but what if you want to see the whole block? Say, the output of "dmidecode" (as root):

dmidecode | awk '/Battery/,/^$/'

Will show me everything following the battery block up to the next block of text. Again, I find this extremely useful when I want to see whole blocks of text based on a pattern, and I don't care to see the rest of the data in output. This could be used against the '/etc/securetty/user' file on Unix to find the block of a specific user. It could be used against VirtualHosts or Directories on Apache to find specific definitions. The scenarios go on for any text formatted in a block fashion. Very handy.

mount.gmailfs none /mount/path/ [-o username=USERNAME[,password=PASSWORD][,fsname=VOLUME]] [-p]
2009-03-28 13:00:47
User: cammarin
Functions: mount
Tags: gmailfs fuse

Packages: gmailfs fuse-utils libfuse2 gvfs-fuse

Config files: /etc/gmailfs/gmailfs.conf; ~/.gmailfs.conf (make a copy from the another one)


fusermount -u /mount/path/

/etc/fstab (Optional):

none /mount/path/ gmailfs

noauto,user[,username=USERNAME,password=PASSWORD,fsname=VOLUME] 0 0


- The options between [] are optional since they already setuped on the config files.

- The '-p' flag shows a prompt for the password entry.

- It's necessary to add the user to the 'fuse' group. You can do that with:

sudo chgrp fuse /dev/fuse


sudo usermod -a -G fuse USER

- The volume name is not needed but highly recommended to avoid file corruption. Also choose a non-trivial name.

- Google doesn't approve the use of Gmail account other than e-mail purposes. So, I recommend the creation of a new account for this.

host -la domain.com
2009-03-28 12:15:16
Functions: host

Perform a dns zone transfer (if is allowed on target dns server) and print result.

2009-03-28 11:43:21
User: mpb

See: "man pwgen" for full details.

Some Linux distros may not have pwgen included in the base distribution

so you maye have to install it (eg in Mandriva Linux: "urpmi pwgen").

sudo firefox -install-global-extension /path/to/add-on
2009-03-28 11:11:12
User: cammarin
Functions: sudo
Tags: firefox

To install a theme use:

sudo firefox -install-global-theme /path/to/theme

You can get the .xpi or .jar file from the versions history on the add-on/theme page.

NOTE: may not work in your system (Debian-based is an example).

mplayer -vo aa <video file>
wget -c -t 1 --load-cookies ~/.cookies/rapidshare <URL>
2009-03-28 09:13:35
User: cammarin
Functions: wget

The download content part.

NOTE: the '-c' seems to not work very well and the download stuck at 99% sometimes. Just finish wget with no problem. Also, the download may restart after complete. You can also cancel. I don't know if it is a wget or Rapidshare glitch since I don't have problems with Megaupload, for example.

UPDATE: as pointed by roebek the restart glitch can be solved by the "-t 1" option. Thanks a lot.

wget --save-cookies ~/.cookies/rapidshare --post-data "login=USERNAME&password=PASSWORD" -O - https://ssl.rapidshare.com/cgi-bin/premiumzone.cgi > /dev/null
2009-03-28 09:12:02
User: cammarin
Functions: wget

In order to do that, first you need to save a cookie file with your account info. These commands do it (maybe you need to create the '.cookies' dir before). Also, you need to check the "Direct downloads" option on the Premium Zone >> Settings tab.

You need to do this once (as long you maintain the file or your Rapidshare Premium account).

apg -a 0 -n 10
2009-03-28 02:28:19
User: acirulli
Tags: vim vi

Within vi allow to empty a text file in one shot

2009-03-28 00:18:39
User: mpb

The vi key sequence !}command will send the file contents from the cursor

to the next blank line as STDOUT to the command specified

and replace that sequence of file lines with the output of the command.

For example: sorting a block of data - !}sort

The sequence !{command will do the same but "upwards" (from the current position towards the start of the file.

chmod +x FILES
sudo chmod -R g=u-w,g+X *
ls -Sl * | head
2009-03-27 23:20:32
User: colinpj
Functions: ls

head by default displays first ten lines of its output. Use 'head -nXX' to display the XX largest files

base64 -d <<< aHR0cDovL3d3dy50d2l0dGVyc2hlZXAuY29tL3Jlc3VsdHMucGhwP3U9Y29tbWFuZGxpbmVmdQo=
2009-03-27 23:20:23
User: stu

apart from not being generalisable to all shells, `Y <<< X` seems nicer to me than `echo X | Y`, e.g.

&lt;&lt;&lt; lol cat;

it reads easier, you type less, and it also looks cool

kill -9 $$
2009-03-27 23:13:53
User: stu
Functions: kill
Tags: history exit

this exits bash without saving the history. unlike explicitly disabling the history in some way, this works anywhere, and it works if you decide *after* issuing the command you don't want logged, that you don't want it logged

... $$ ( or ${$} ) is the pid of the current bash instance

this also works perfectly in shells that don't have $$ if you do something like

kill -9 `readlink /proc/self`
netstat -atn | awk ' /tcp/ {printf("%s\n",substr($4,index($4,":")+1,length($4) )) }' | sed -e "s/://g" | sort -rnu | awk '{array [$1] = $1} END {i=32768; again=1; while (again == 1) {if (array[i] == i) {i=i+1} else {print i; again=0}}}'
2009-03-27 20:38:43
User: mpb
Functions: awk netstat sed sort

Some commands (such as netcat) have a port option but how can you know which ports are unused?