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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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Commands using sleep from sorted by
Terminal - Commands using sleep - 254 results
while true ; do du -sk testfile ; sleep 10 ; done
2009-08-14 11:39:52
User: Solaris
Functions: du sleep true

This command produces the output of "du -sk testfile" in every 10 seconds. You can change the command to be whatever you want.

while true ; do IFS="" read i; echo "$i"; sleep .01; done < <(tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]")
2009-07-22 03:59:07
Functions: dd echo grep read sleep tr true
Tags: color

Same as above but slooooow it down

yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
sleep 5h && rhythmbox path/to/song
2009-06-25 19:15:19
User: becomingGuru
Functions: sleep

Sleep 5h and plays the song as a wake up alarm

while true; do { $(which logger) -p local4.notice `free -m | grep Mem`; sleep 60; } done &
2009-06-22 00:29:53
User: Neo23x0
Functions: grep sleep which

Uses logger in a while loop to log memory statistics frequently into the local syslog server.

chronic () { t=$1; shift; while true; do $@; sleep $t; done & }
2009-06-13 05:57:54
User: rhythmx
Functions: sleep

Chronic Bash function:

chronic 3600 time # Print the time in your shell every hour chronic 60 updatedb > /dev/null # update slocate every minute

Note: use 'jobs' to list background tasks and fg/bg to take control of them.

while (( $i != 0 )) { smbstatus; sleep 5; clear }
2009-06-03 13:26:30
Functions: clear sleep
Tags: unix samba zsh

See smbstatus Output within a 5 second interval (for monitoring smb access)

while [ i != 0 ]; do sleep 1 | dialog --clear --gauge "Quality: " 0 0 $(cat /proc/net/wireless | grep $WIRELESSINTERFACE | awk '{print $3}' | tr -d "."); done
2009-05-31 16:09:23
User: ncaio
Functions: awk cat grep sleep tr

The variable WIRELESSINTERFACE indicates your wireless interface

sudo pmset schedule sleep "08/31/2009 00:00:00"
2009-05-14 09:31:32
User: hobzcalvin
Functions: sleep sudo

Schedule your Mac to sleep at any future time.

Also wake, poweron, shutdown, wakeorpoweron. Or repeating with

sudo pmset repeat wakeorpoweron MTWRFSU 7:00:00

Query with

pmset -g sched

Lots more at http://www.macenterprise.org/articles/powermanagementandschedulingviathecommandline

while :; do xfconf-query -c xfce4-desktop -p /backdrop/screen0/monitor0/image-path -s "$(find <image-directory> -type f -iregex '.*\.\(bmp\|gif\|jpg\|png\)$' | sort -R | head -1)"; sleep 30m; done
2009-04-30 03:09:52
Functions: sleep
Tags: bash find xfce

Change your wallpaper every thirty minutes (or however long you like, I suppose) to a randomly selected image in a directory and subdirectories. Bear in mind this is not safe to use if anyone else has write access to your image directory.

while true; do ifconfig eth0 | grep "inet addr:"; sleep 60; done;
2009-04-01 19:29:28
User: bandit36
Functions: grep ifconfig sleep
Tags: script while loop

You can use this to loop any command to periodically see the output.

while true; do [YOUR COMMAND HERE]; sleep [# of seconds]; done;

Alternatively, you can put it in a simple shell script to save typing!


while true; do $1; sleep $2; done;

/path/to/script.sh "ifconfig eth0 | grep 'inet addr:'" 60
while true; do [ "$(ping -c1W1w1 server-or-ip.com | awk '/received/ {print $4}')" != 1 ] && beep; sleep 1; done
2009-03-31 20:47:56
User: sudopeople
Functions: sleep

pings a server once per second, and beeps when the server is unreachable.

Basically the opposite of:

ping -a server-or-ip.com

which would beep when a server IS reachable.

You could also substitute beep with any command, which makes this a powerful alternative to ping -a:

while true; do [ "$(ping -c1W1w1 server-or-ip.com 2>/dev/null | awk '/received/ {print $4}')" = 1 ] && date || echo 'server is down!'; sleep 1; done

which would output the date and time every sec until the ping failed, in which case it would echo.


Requires beep package.

May need to run as root (beep uses the system speaker)

Tested on Ubuntu which doesn't have beep out of the box...

sudo apt-get install beep
while true; do X=$Y; sleep 1; Y=$(ifconfig eth0|grep RX\ bytes|awk '{ print $2 }'|cut -d : -f 2); echo "$(( Y-X )) bps"; done
while [ 1 ]; do echo -n "`date +%F_%T`" ; vmstat 1 2 | tail -1 ; sleep 4; done
2009-03-26 19:16:55
User: plasticboy
Functions: echo sleep tail vmstat

See man vmstat for information about the statistics.

This does the same thing without the timestamp:

vmstat 5
while true; do date; sleep 1; done
2009-03-23 22:44:59
User: cbetts
Functions: sleep

Handy if all you have is a console session or tty.

lockstat -I -i 977 -s 30 -h sleep 1 > /tmp/profile.out
2009-03-13 13:17:53
User: garylittle
Functions: sleep

Lockstat will sample the kernel 977 times per second, and print out the functions that it sees executing on the CPU during the sample. The -s 10 switch tells lockstsat to not only print that function, but also show the call stack (up to 10 deep).

for i in $(seq 0 5) ; do echo "5 - $i" | bc -l ; sleep 60 ; done && echo "bye, bye" && shutdown -h now
2009-03-13 12:16:35
User: arctarus
Functions: bc echo seq shutdown sleep

command to turn off your computer when you go home and can not wait

for person in Alex Bruce Fred Kathy Vicki Victoria ; do say -v $person "Hello, my name is $person"; sleep 1; done
2009-03-09 15:42:13
User: haivu
Functions: sleep
Tags: Os X

Listen to different voices in the system--useful for picking the voice you like

doloop() { DONT=/tmp/do-run-run-run; while true; do touch $DONT; (sleep 30; rm $DONT;) & $1 ; if [ -e $DONT ]; then echo restarting too fast; return ; fi ; done }
2009-02-21 02:11:18
User: evil_otto
Functions: echo return rm sleep touch

This runs a command continuously, restarting it if it exits. Sort of a poor man's daemontools. Useful for running servers from the command line instead of inittab.

while [ 1 ]; do curl -s -u username:password http://twitter.com/statuses/friends_timeline.rss|grep title|sed -ne 's/<\/*title>//gp' | head -n 6 |festival --tts; sleep 300;done
2009-02-20 20:20:21
User: tomwsmf
Functions: head sleep

Pump up the chatter, run this script on a regular basis to listen to your twitter timeline.

This is a rough first cut using several cli clips I have spotted around. There is no facility to not read those things already read to you. This could also easily be put in a loop for timed onslaught from the chatterverse, though I think it might violate several pointsof the Geneva Convention

UPDATE - added a loop, only reads the first 6 twits, and does this every 5 mins.

$(STEEP=300; sleep $STEEP; xmessage "Your tea is done") &
2009-02-19 20:10:49
User: sud0er
Functions: sleep

wrapping the snippet in $( )& puts the whole thing in the background so you don't tie up your login session.

for (( i = 10; i > 0; i-- )); do echo "$i"; sleep 1; done
2009-02-18 20:31:46
User: mestr
Functions: echo sleep

Countdown from 10 or whatever you want:)

while [ 0 ]; do expr 2365200000 \- `date +%s` \- `date --date "YYYY-mm-dd HH:MM:ss" +%s`; sleep 1; clear; done
2009-02-13 20:02:37
User: wwest4
Functions: expr sleep

watch the seconds of your life tick away - replace YYYY-mm-dd HH:MM:ss w/ your birthtime.

sleep 3m; play bigben.wav
2009-02-13 13:20:13
User: legba7
Functions: sleep

plays wave file after 3 minutes

while [ ! -f /tmp/stop ]; do ssh -o ExitOnForwardFailure=yes -R 2222:localhost:22 target "while nc -zv localhost 2222; do sleep 5; done"; sleep 5;done