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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using sleep from sorted by
Terminal - Commands using sleep - 240 results
while sleep 1; do foo; done
2012-09-14 20:21:04
User: lowbatteries
Functions: sleep

For use when you can't use "watch" (user-defined functions, aliases). This isn't mine - its an alternate posted in the comments by flatcap, and is the shortest and easiest to remember.

alarmclock() { [ $1 ] || echo Parameter TIME is missing. 1>&2 && return 1 ; ( sleep $1 ; for x in 9 8 7 6 5 4 3 2 1 ; do for y in `seq 0 $[ 10 - $x ] ` ; do printf "\a"; sleep 0.$x ; done ; done ) & }
2012-08-16 15:35:15
User: lkj
Functions: echo printf return sleep

usage: alarmclock TIME

TIME is a sleep(1) parameter which tells function how long to wait until raise the alarm.

sleep 3;import -window root output.png
while x=0; do foo ; sleep 1 ; done
2012-07-11 13:22:21
User: eastwind
Functions: sleep

repeat a command every X seconds , output show the creation of partition image using fsarchiver, each line show the size of the image.

hourglass(){ trap 'tput cnorm' 0 1 2 15 RETURN;local s=$(($SECONDS +$1));(tput civis;while (($SECONDS<$s));do for f in '|' '\' '-' '/';do echo -n "$f";sleep .2s;echo -n $'\b';done;done;);}
2012-06-21 05:40:22
User: AskApache
Functions: echo sleep tput trap

Displays an animated hourglass for x amount of seconds

while pgrep wget || sudo shutdown -P now; do sleep 1m; done
slow () { [ -n $1 ] && while kill -STOP $1; do sleep 1; kill -CONT $1; sleep 1; done }
2012-05-16 19:16:50
User: makidoko
Functions: kill sleep
Tags: io

compare to alternative :

- directly tests the -STOP of the process to continue or stop loop,

- background operator should be set (or not) at the call of the function

For extension i suggest a slowPID() based on kill like above and a slowCMD based on killall.

slow () { [ -n $1 ] && while ps -p $1 >/dev/null ; do kill -STOP $1; sleep 1; kill -CONT $1; sleep 1; done & }
2012-05-16 12:13:30
User: igorfu
Functions: kill ps sleep
Tags: io

Some IO intensive process make the system unresponsive. This function periodically starts/stops a process, which hopefully releases some resources for other activities.

This function is useful when ionice is not available

while true; do sudo cat /dev/input/mouse0|read -n1;streamer -q -o /tmp/cam.jpeg -s 640x480 > /dev/null 2>&1; sleep 10;done
2012-04-22 01:51:30
Functions: cat read sleep sudo
Tags: cat streamer

This takes a webcam picture every everytime the mouse is moved (waits 10 seconds between checking for movement) and stores the picture wherever you want it.


Use in conjunction with a dropbox type application to see who is using your computer

Use /dev/input/mice if /dev/input/mouse* doesn't work

Use the bones of this to make a simple screensaver

sleep 15 ; `echo "done" | mail -s "done" 4158575309@txt.att.net`
2012-04-16 01:28:16
User: vajrapani666
Functions: mail sleep

Replace "4158575309@txt.att.net" with your carrier's SMS gateway identifier. The one in the sample is for AT&T. More here https://en.wikipedia.org/wiki/List_of_SMS_gateways. Helpful for getting notifications about long running commands. ";" executes regardless of exit status of last command. && will only notify you if the command succeeds.

(set -o noglob;while sleep 0.05;do for r in `grep -ao '[[:print:]]' /dev/urandom|head -$((COLUMNS/3))`;do [ $((RANDOM%6)) -le 1 ] && r=\ ;echo -ne "\e[$((RANDOM%7/-6+2));32m $r ";done;echo;done)
2012-04-13 02:09:10
User: khopesh
Functions: echo head set sleep

A tweak using Patola's code as a base, this full-width green matrix display has all the frills (and all the printable characters).

You don't need the surrounding parens if you don't care about losing globbing capabilities. Z-shell (/bin/zsh) needs neither the parens nor the `set -o noglob`

Screen shot (animated): http://desmond.imageshack.us/Himg32/scaled.php?server=32&filename=matrixh.gif&res=landing

If it's too slow, try lowering the `sleep 0.05` or even replacing it with `true` (which is faster than `sleep 0`).

I squashed it as narrow as I could to conserve space, though somebody could probably squeeze a char or two out.


yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
while [ 1 ]; do tail /var/log/httpd/error_log; sleep 2; clear; done
watch() { while true; do echo "<Ctrl+V><Ctrl+L>Every 2.0s: $@"; date; eval "$@"; sleep 2; done }
2012-03-07 09:30:15
User: hfs
Functions: echo eval sleep watch
Tags: watch


watch ls -l

Basic but usable replacement for the "watch" command for those systems which don't have it (e.g. the Solaris I'm trapped on).

Type Ctrl+V to escape the following Ctrl+L which clears the screen. It will be displayed as "^L".

for ((x=0;;x+=5)); do sleep 5; hours=$(($x/3600)); minutes=$(($x%3600/60)); seconds=$(($x%60)); echo "$hours hours $minutes minutes $seconds seconds have elapsed" | festival --tts & done
2012-03-06 22:58:43
User: mrklaw
Functions: echo sleep

Says time every 5 seconds in hours, minutes and seconds using festival.

for ((x=0;;x+=5)); do sleep 5; echo $x | festival --tts & done
2012-03-06 21:17:51
User: mrklaw
Functions: echo sleep

works the same, but uses festival instead of espeak

watch() { if [ -z "$1" ]; then echo "usage: watch interval command" return fi sec=$1 shift while test :; do clear; date=$(date); echo -e "Every "$sec"s: $@ \t\t\t\t $date"; echo $@; sleep $sec; done }
r="readlink /proc/`pgrep -o mplayer`/fd/3";while [ -e "`$r`" ];do if [ "$f" = "`$r`" ];then sleep 1;else f="`$r`";notify-send " $f";fi;done
2012-02-26 06:49:16
User: aix
Functions: sleep

Will finish automagically when mplayer quits. Can be run from any directory.

It seems to finish by it self rarely, probably because of some timing issue? There's probably a way around that which I can't think of right now

dd if=/dev/urandom of=file.img bs=4KB& sleep 1 && pid=`pidof dd`; while [[ -d /proc/$pid ]]; do kill -USR1 $pid && sleep 10 && clear; done
2012-02-23 01:45:53
Functions: dd kill sleep

The previously-posted one-liner didn't work for me for whatever reason, so I ended up doing this instead.

for ((x=0;;x+=5)); do sleep 5; espeak $x & done
2012-02-22 00:26:57
User: adeverteuil
Functions: sleep
Tags: audio bash timer

Useful contexts :

You are doing yoga or some other physical training in which you are holding a position.

Or you practice the pomodoro productivity technique.

Or your girlfriend said "We're leaving in 40 minutes".

Design details:

sleep executes before espeak to give you a 5 seconds head start.

espeak is run in the background so it doesn't mess up the timing.

export GREP_COLOR='1;32';while [ true ]; do head -n 100 /dev/urandom; sleep .1; done | hexdump -C | grep --color=auto "ca fe"
sayspeed() { for i in $(seq 1 `echo "$1"|wc -c`); do echo -n "`echo $1 |cut -c ${i}`"; sleep 0.1s; done; echo "";}
2012-02-11 05:51:42
User: kundan
Functions: echo seq sleep wc

change the time that you would like to have as print interval

and just use it to say whatever you want to

while true; do curl -s http://sensiblepassword.com/?harder=1 | tail -n 15 | head -n 1 | sed 's;<br/>;;' | cut -c 5- | cb; sleep 1; done
2012-01-30 20:52:14
User: supervacuo
Functions: cut head sed sleep tail

Use the excellent sensiblepasswords.com to a generate random (yet easy-to-remember) password every second, and copy it to the clipboard. Useful for generating a list of passwords and pasting them into a spreadsheet.

This script uses "madebynathan"'s "cb" function (http://madebynathan.com/2011/10/04/a-nicer-way-to-use-xclip/); you could also replace "cb" with

xclip -selection c

Remove "while true; do" and "; done" to generate and copy only 1 password.

for i in `wget -O url|grep '<a rel="nofollow"'|grep http|sed 's|.*<a rel="nofollow" class="[^"]\+" href="[^"]*https\?://\([^/]\+\)[^"]*">[^<]\+</a>.*|\1|'`;do if test -n "$(whois $i|grep -i godaddy)";then echo $i uses GoDaddy;fi;sleep 20;done
check(){ power=$(acpi -a) ; if [[ $power == *on-line* ]] ; then echo "supply is on"; else echo "somebody is steeling your laptop"; amixer -c0 set Master 100+ unmute ; mpg123 nuclear-alarm.mp3 ; fi } ;while true; do check ; sleep 2 ; done
2011-12-10 13:42:52
User: hoodie

Checks whether your power supply is still plugged in.

If not it will trigger an alarm at maximum volume.