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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 sleep from sorted by
Terminal - Commands using sleep - 254 results
while true ; do fswebcam -d /dev/video0 -r 1280x1024 -F 15 - | uuencode $(date +\%Y\%m\%d\%H\%M).jpeg | mail -s "Video surveillance" [email protected] ; sleep 300 ; done
2016-08-09 14:22:45
User: pascalv
Functions: date mail sleep true uuencode

This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail.

Some systems support

mail -a "References: "

so that all video surveillance emails are grouped in a single email thread.

To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!)

For instance with Gmail, emails sent to [email protected] can be filtered with "Matches: DeliveredTo:[email protected]"

while true ; do wget --quiet --no-check-certificate --post-data 'login=my_account_number&password=my_password&submit=Valider' 'https://wifi.free.fr/Auth' -O '/dev/null' ; sleep 600; done
2016-07-23 16:34:42
User: pascalv
Functions: sleep true wget
Tags: wifi France

(In French) Connection aux hotspots FreeWifi, et maintien de la connection active

while true; do A=$(stat -c%s FILE); sleep 1; B=$(stat -c%s FILE); echo -en "\r"$(($B-$A))" Bps"; done
2016-06-27 20:39:06
User: Zort
Functions: echo sleep stat

Muestra el crecimiento de un archivo por segundo.

Cambia el texto "FILE" por el nombre del archivo a monitorear.

Comando STAT

while true; do A=$(ls -l FILE | awk '{print $5}'); sleep 1; B=$(ls -l FILE | awk '{print $5}'); echo -en "\r"$(($B-$A))" Bps"; done
2016-06-27 20:33:02
User: Zort
Functions: awk echo ls sleep

Muestra el crecimiento de un archivo por segundo.

Cambia el texto "FILE" por el nombre del archivo a monitorear.

Comando LS + AWK

while(1){while((date -f ss)%10-gt0){sleep -m 300} echo "$(date -u %s) $((curl|%{$_ -replace '\D+\n',''})">>modemlog.txt;sleep 1;echo .}
2015-12-24 02:12:10
User: omap7777
Functions: date echo sleep

IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type


Create a log file of your Motorola Surfboard SB6141 downstream signal strengths.

Uses the built-in curl to request signal strength data from your SB6141 cable modem.

HTML page has the signal strength numbers for the 8 downstreams.

Some HTML/DOM processing parses out the 8 values from the above page.

The eight extracted signal strengths are then logged to a file.

A small while-loop watches the clock & repeats the process every 10 seconds.

while true; do (echo -n $(date +"%F %T"):\ ; xwininfo -id $(xprop -root|grep "ACTIVE_WINDOW("|cut -d\ -f 5) | grep "Window id" | cut -d\" -f 2 ) >> logfile; sleep 60; done
2015-09-23 23:00:14
User: BeniBela
Functions: cut date echo grep sleep

This logs the titles of the active windows, thus you can monitor what you have done during which times. (it is not hard to also log the executable name, but then it is gets too long)

while true; do nc -z localhost 3333 >|/dev/null || (ssh -NfL 3333:REMOTE_HOST:5432 [email protected]_HOST); sleep 15; done
2015-09-21 02:25:49
User: rxw
Functions: sleep ssh

Check if SSH tunnel is open and open it, if it isn't.

NB: In this example, 3333 would be your local port, 5432 the remote port (which is, afaik, usually used by PostgreSQL) and of course you should replace REMOTE_HOST with any valid IP or hostname. The example above let's you work on remote PostgreSQL databases from your local shell, like this:

psql -E -h localhost -p 3333
while cat energy_now; do sleep 1; done |awk -v F=$(cat energy_full) -v C=60 'NR==1{P=B=$1;p=100/F} {d=$1-P; if(d!=0&&d*D<=0){D=d;n=1;A[0]=B=P}; if(n>0){r=g=($1-B)/n;if(n>C){r=($1-A[n%C])/C}}; A[n++%C]=P=$1; printf "%3d %+09.5f %+09.5f\n", p*$1, p*g, p*r}'
2015-09-19 15:45:40
User: sqweek
Functions: awk cat printf sleep

Needs to be run in a battery sysfs dir, eg. /sys/class/power_supply/BAT0 on my system.

Displays the battery's current charge and the rate per-second at which energy is {dis,}charging. All values are displayed as percentages of "full" charge.

The first column is the current charge. The second is the rate of change averaged over the entire lifetime of the command (or since the AC cable was {un,}plugged), and the third column is the rate of change averaged over the last minute (controlled by the C=60 variable passed to awk).

The sample output captures a scenario where I ran 'yes' in another terminal to max out a CPU. My battery was at 76% charge and you can see the energy drain starts to rise above 0.01% per-second as the cpu starts working and the fan kicks in etc. While idle it was more like 0.005% per-second.

I tried to use this to estimate the remaining battery life/time until fully charged, but found it to be pretty useless... As my battery gets more charged it starts to charge slower, which meant the estimate was always wrong. Not sure if that's common for batteries or not.

while true; do date; ps auxf | awk '{if($8=="D") print $0;}'; sleep 1; done
pvl() { (for i in "$@"; do youtube-dl -q --max-downloads 1 --no-playlist "$i" -o - | mplayer -vo null /dev/fd/3 3<&0 </dev/tty; sleep .5; done); }
2015-07-14 04:44:36
User: snipertyler
Functions: sleep

pvl 'link1' 'link2' 'link3'

Play Youtube, Vimeo, etc links without visual elements.

Great for music videos when you just want the audio.

You can control mplayer with this!

Hit Ctrl-C twice to exit (if you're playing multiple files)

while [ $(( $(date +%s) - $(stat -c %Y FILENAME) )) -lt 10 ]; do sleep 1; done; echo DONE
2015-05-09 12:30:13
User: flatcap
Functions: date echo sleep stat

This loop will finish if a file hasn't changed in the last 10 seconds.


It checks the file's modification timestamp against the clock.

If 10 seconds have elapsed without any change to the file, then the loop ends.


This script will give a false positive if there's a 10 second delay between updates,

e.g. due to network congestion


How does it work?

'date +%s' gives the current time in seconds

'stat -c %Y' gives the file's last modification time in seconds

'$(( ))' is bash's way of doing maths

'[ X -lt 10 ]' tests the result is Less Than 10

otherwise sleep for 1 second and repeat


Note: Clever as this script is, inotify is smarter.

sleep 10 & perl -e [email protected]=qw(-Ooooo \oOooo |ooOoo /oooOo -ooooO \oooOo |ooOoo /oOooo);while(kill 0,'$!'){ print "\r",$s[$t++%($#s+1)];select(undef,undef,undef,0.2);}'
while [ "$(ls -l --full-time TargetFile)" != "$a" ] ; do a=$(ls -l --full-time TargetFile); sleep 10; done
2015-05-09 03:19:49
User: dmmst19
Functions: ls sleep

Here's a way to wait for a file (a download, a logfile, etc) to stop changing, then do something. As written it will just return to the prompt, but you could add a "; echo DONE" or whatever at the end.

This just compares the full output of "ls" every 10 seconds, and keeps going as long as that output has changed since the last interval. If the file is being appended to, the size will change, and if it's being modified without growing, the timestamp from the "--full-time" option will have changed. The output of just "ls -l" isn't sufficient since by default it doesn't show seconds, just minutes.

Waiting for a file to stop changing is not a very elegant or reliable way to measure that some process is finished - if you know the process ID there are much better ways. This method will also give a false positive if the changes to the target file are delayed longer than the sleep interval for any reason (network timeouts, etc). But sometimes the process that is writing the file doesn't exit, rather it continues on doing something else, so this approach can be useful if you understand its limitations.

while kill -0 0; do timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for _ in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'; done
2015-05-07 19:13:08
User: anapsix
Functions: bash echo kill seq sleep

alternatively, run the spinner for 5 seconds:

timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for j in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'

clear; while sleep 1; do d=$(date +"%H:%M:%S"); e=$(echo "toilet -t -f mono12 $d");tput setaf 1 cup 0; eval $e; tput setaf 4 cup 8; eval "$e -F flop";tput cup 0; done
perl -e 'for(;;sleep 1){printf"\r"."%.4b "x6,split"",`date +%H%M%S`}'
clear;while true;sleep 1;do for((a=1;a<=$(tput cols)/3;a++));do tput cup 0 $a;echo " " $(date);done;sleep 1;for((a;a>=1;a--));do tput cup 0 $a;echo $(date) " ";done;done
while sleep 1; do if [ $(echo "$(cat /proc/loadavg | cut -d' ' -f1) > .8 " | bc) -gt 0 ]; then echo -e "\n\a"$(date)" \e[5m"$(cat /proc/loadavg)"\e[0m"; ps aux --sort=-%cpu|head -n 5; fi; done
2014-12-08 15:44:40
User: tyzbit
Functions: cat echo head ps sleep

This checks the system load every second and if it's over a certain threshold (.8 in this example), it spits out the date, system loads and top 4 processes sorted by CPU.

Additionally, the \a in the first echo creates an audible bell.

speakwhenup() { [ "$1" ] && PHOST="$1" || return 1; until ping -c1 -W2 $PHOST >/dev/null 2>&1; do sleep 5s; done; espeak "$PHOST is up" >/dev/null 2>&1; }
2014-11-26 10:22:18
User: aguslr
Functions: ping return sleep
Tags: ping beep espeak

This allows for sleeping in between pings. Also, espeak needs to be installed.

sleep 10 & wait $!
2014-09-25 13:33:51
User: yorkou
Functions: sleep wait

A nice way to interrupt a sleep with a signal.

(echo -e '\x06\x00\x00\x00\x00\x00\x01\x01\x00'; sleep 1)|nc -c $host 25565
for a in $(seq 15); do (xset led 3);(xset -led 3);sleep .9;done
cat h.txt| while read line; do curl -s -X POST 'https://www.virustotal.com/vtapi/v2/file/report' --form apikey="APIKEY" --form resource="$line"|awk -F'positives\":' '{print "VTHits"$2}'|awk -F' ' '{print $1" "$2$5$6}'|sed 's/["}]//g' && sleep 15; done
alias alive='(while true; do ping -c 4 > /dev/null 2>&1 ; sleep 300 ; done)'
2014-06-13 06:13:57
User: DarkXDroid
Functions: alias ping sleep

Everytime You Run Bash It Will Run And Send The Command To Background In A Loop Forever. This Is Useful In Android To Avoid Getting Discconnected While Using ADB Or Other Services Like SSH By Being Inactive For Long Periods Of Time. In My Case I Get Bash Full Suport Only Through ADB And Also A Decent Python Interpreter Using Python For Android.

NUM=-1; while NUM=`echo $NUM + 1 | bc`; do echo $NUM && sleep 1; done
2014-06-07 20:48:45
User: tomivs
Functions: echo sleep

Chronometer using the bc calculator.