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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!

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 using echo from sorted by
Terminal - Commands using echo - 1,318 results
echo sortmeplease | grep -o . | sort | tr -d '\n'; echo
2009-09-03 00:52:49
User: MrMerry
Functions: echo grep sort tr

Sorts a character string, using common shell commands.

echo "5 k 3 5 / p" | dc
2009-09-03 00:21:54
User: xamaco
Functions: echo

using bc is for sissies. dc is much better :-D

Polish notation will rule the world...

for dnsREC in $(curl -s http://www.iana.org/assignments/dns-parameters |grep -Eo ^[A-Z\.]+\ |sed 's/TYPE//'); do echo -n "$dnsREC " && dig +short $dnsREC IANA.ORG; done
xmms2 pause && echo "xmms2 play" | at now +5min
2009-08-30 04:35:10
User: Vrekk
Functions: at echo

you can also run "xmms2 pause & at now +5min

echo "${PATH//:/$'\n'}"
for i in 192.168.1.{61..71};do ping -c 1 $i &> /dev/null && echo $i;fi;done
2009-08-26 06:04:24
User: AlecSchueler
Functions: echo ping
Tags: Network ssh bash

If you need to ssh into a computer on the local network but you're unsure of the ip to use, then ping them and see if you get a response. If you do, print out the address you got it from. Adjust the range to suit your network.

echo "xmms2 play" | at 6:00
2009-08-26 04:20:24
User: Vrekk
Functions: at echo

Nice little alarm clock to wake you up on time (hopefully).

You can also do 'echo "vlc path/to/song" | at 6:00

echo "0t${currentEpoch}=Y" | /usr/bin/adb
2009-08-25 12:17:01
User: verboEse
Functions: echo

this works on Solaris, so not better than the "only-GNU"-tool :-(

I think, there is no one-liner for this, that will work on all *nix-es

echo "aBcDeFgH123" | tr a-z A-Z
echo 1234567890 | awk '{ print strftime("%c", $0); }'
2009-08-25 09:37:54
User: alvinx
Functions: awk echo

- convert unixtime to human-readable with awk

- useful to read logfiles with unix-timestamps, f.e. squid-log:

sudo tail -f /var/log/squid3/access.log | awk '{ print strftime("%c ", $1) $0; }

echo `date +%m/%d/%y%X |awk '{print $1;}' `" => "` cat /proc/acpi/thermal_zone/THRM/temperature | awk '{print $2, $3;}'` >> datetmp.log
2009-08-24 21:26:29
User: ninadsp
Functions: awk cat echo

Uses the data in the /proc system, provided by the acpid, to find out the CPU temperature. Can be run on systems without lm-sensors installed as well.

y=http://www.youtube.com;for i in $(curl -s $f|grep -o "url='$y/watch?v=[^']*'");do d=$(echo $i|sed "s|url\='$y/watch?v=\(.*\)&.*'|\1|");wget -O $d.flv "$y/get_video.php?video_id=$d&t=$(curl -s "$y/watch?v=$d"|sed -n 's/.* "t": "\([^"]*\)",.*/\1/p')";done
2009-08-22 21:31:29
User: matthewbauer
Functions: echo grep sed

This will download a Youtube playlist and mostly anything http://code.google.com/apis/youtube/2.0/reference.html#Video_Feeds

The files will be saved by $id.flv

pgrep -u `id -u` firefox-bin || find ~/.mozilla/firefox -name '*.sqlite'|(while read -e f; do echo 'vacuum;'|sqlite3 "$f" ; done)
2009-08-22 10:36:05
User: kamathln
Functions: echo find read

Sqlite database keeps collecting cruft as time passes, which can be cleaned by the 'vacuum;' command. This command cleans up the cruft in all sqlite files relating to the user you have logged in as. This command has to be run when firefox is not running, or it will exit displaying the pid of the firefox running.

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
Tags: sort cut for groups

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

echo $(( $RANDOM % 10 + 1 ))
echo init 0 | at now + 2 hours
echo "scale=4; 3 / 5" | bc
2009-08-21 21:51:46
User: foob4r
Functions: echo

allows you to use floating point operations in shell scripts

sync; echo 3 > /proc/sys/vm/drop_caches
watch() { t=$1; shift; while test :; do clear; date=$(date); echo -e "Every "$t"s: $@ \t\t\t\t $date"; $@; sleep $t; done }
watch() { while test :; do clear; date=$(date); echo -e "Every "$1"s: $2 \t\t\t\t $date"; $2; sleep $1; done }
echo sleep() begins: %TIME% && FOR /l %a IN (10,-1,1) do (ECHO 1 >NUL %as&ping -n 2 -w 1>NUL) && echo sleep() end: %TIME%
2009-08-19 13:43:09
User: pfredrik
Functions: echo

Enable 'sleep' function in Windows environment where this does not exist, although not exact in time. (there is a delay for each ping) This is a simple way to separate commands with a time-period.

S=$SSH_TTY && (sleep 3 && echo -n 'Peace... '>$S & ) && (sleep 5 && echo -n 'Love... '>$S & ) && (sleep 7 && echo 'and Intergalactic Happiness!'>$S & )
2009-08-19 07:57:16
User: AskApache
Functions: echo sleep

Ummmm.. Saw that gem on some dead-head hippies VW bus at phish this summer.. It's actually one of my favorite ways of using bash, very clean. It shows what you can do with the cool advanced features like job control, redirection, combining commands that don't wait for each other, and the thing I like the most is the use of the ( ) to make this process heirarchy below, which comes in very handy when using fifos for adding optimization to your scripts or commands with similar acrobatics.


1 gplovr 30667 1 wait 1324 1 -bash

0 gplovr 30672 30667 - 516 3 \_ sleep 3

1 gplovr 30669 1 wait 1324 1 -bash

0 gplovr 30673 30669 - 516 0 \_ sleep 5

1 gplovr 30671 1 wait 1324 1 -bash

0 gplovr 30674 30671 - 516 1 \_ sleep 7

echo "nohup command rm -rf /phpsessions 1>&2 &>/dev/null 1>&2 &>/dev/null&" | at now + 3 hours 1>&2 &>/dev/null
2009-08-18 07:31:17
User: AskApache
Functions: at echo

This is helpful for shell scripts, I use it in my custom php install script to schedule to delete the build files in 3 hours, as the php install script is completely automated and is made to run slow.

Does require at, which some environments without crontab still do have.

You can add as many commands to the at you want. Here's how I delete them in case the script gets killed. (trapped)

atq |awk '{print $1}'|xargs -iJ atrm J &>/dev/null

urls=('www.ubuntu.com' 'google.com'); for i in ${urls[@]}; do http_code=$(curl -I -s $i -w %{http_code}); echo $i status: ${http_code:9:3}; done
echo "import this" | python
2009-08-15 09:42:36
User: loquitus
Functions: echo

Very very cool list of quotations and directives on pythonic programming. I love them and they are sure applicable in C++ too, and for most any programming, really.