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Commands using sleep from sorted by
Terminal - Commands using sleep - 255 results
while (( 1==1 )); do du -c . >> output.log; sleep 2; done; tail -f output.log
2010-07-12 17:23:45
User: aceiro
Functions: du sleep tail

this command shows the space used in postgres directory.

c=0; n=8; while true; do r=`echo $RANDOM%5 |bc`; echo "sleep $r"; sleep $r& 2>&1 >/dev/null && ((c++)); [ `echo "$c%$n" | bc` -eq 0 ] && echo "$c waiting" && wait; done
2010-07-08 13:56:28
User: cp
Functions: echo sleep

the block of the loop is useful whenever you have huge junks of similar jobs, e.g., convert high res images to thumbnails, and make usage out of all the SMP power on your compute box without flooding the system.

note: c is used as counter and the random sleep

r=`echo $RANDOM%5 |bc`; echo "sleep $r"; sleep $r

is just used as a dummy command.

sleep 6s && notify-send -t 10000 -u critical "remember to think" &
2010-07-01 02:17:24
User: zed
Functions: sleep

This will be seen through your system's visual notification system, notify-osd, notification-daemon, etc.


sleep accepts s,m,h,d and floats (date; sleep .25m; date)


notify-send (-t is in milliseconds && -u low / normal / critical)

man notify-send for more information


notification-daemon can use b/i/u/a HTML

function countdown { case "$1" in -s) shift;; *) set $(($1 * 60));; esac; local S=" "; for i in $(seq "$1" -1 1); do echo -ne "$S\r $i\r"; sleep 1; done; echo -e "$S\rBOOM!"; }
2010-06-30 12:20:01
User: kniht
Functions: echo seq set sleep
Tags: timer counter

The biggest advantage over atoponce's nifty original is not killing the scrollback. Written assuming bash, but shouldn't be terribly difficult to port to other shells. S should be multiple spaces, but I can't get commandlinefu to save/show them properly, any help?

sleep 8h && while [ 1 ] ; do date "+Good Morning. It is time to wake up. The time is %I %M %p" | espeak -v english -p 0 -s 150 -a 100 ; sleep 1m; done
2010-06-23 17:34:54
User: copremesis
Functions: date sleep

This ran on a ubuntu box using espeak for speaking text with the bash shell. On a mac you should use 'say'. Also you can change your alarm interval and your snooze interval which are currently 8 hours and 1 minute. I would run this via cron yet it's easier to disable if you run it as a command like this :P

i=$((15*60)); while [ $i -gt 0 ]; do clear; echo $i | figlet; sleep 1; i=$(($i-1)); done;
2010-06-22 17:49:36
User: atoponce
Functions: echo sleep
Tags: figlet timer

Requires figlet. Other than that, this should be portable enough across all the Bourne-compatible shells (sh, bash, ksh, zsh, etc).

Produces a massive number using figlet that counts down the number of seconds for any given minute interval. For example, here's a 4-minute timer:

i=$((4*60)); while [ $i -gt 0 ]; do clear; echo $i | figlet; sleep 1; i=$(($i-1)); done;

And a 1-minute timer:

i=$((1*60)); while [ $i -gt 0 ]; do clear; echo $i | figlet; sleep 1; i=$(($i-1)); done;
MIN=1 && for i in $(seq $(($MIN*60)) -1 1); do echo -n "$i, "; sleep 1; done; echo -e "\n\nBOOOM! Time to start."
2010-06-20 15:19:12
User: atoponce
Functions: echo seq sleep
Tags: timer counter

Simple countdown clock that should be quite portable across any Bourne-compatible shell. I used to teach for a living, and I would run this code when it was time for a break. Usually, I would set "MIN" to 15 for a 15-minute break. The computer would be connected to a projector, so this would be projected on screen, front and center, for all to see.

while true;do clear;echo -n Current\ `grep voltage /proc/acpi/battery/BAT0/state | awk '{print $2" "$3" "$4}'`;for i in `seq 1 5`;do sleep 1;echo -n .;done;done
IFS=`echo -en "\n\b"`; for i in $(curl http://feeds.digg.com/digg/container/technology/popular.rss | grep '<title>' | sed -e 's#<[^>]*>##g' | tail -n10); do echo $i; echo $i | sed 's/^/Did you hear about /g' | say; sleep 30; done
2010-06-07 22:16:19
User: echosedawk
Functions: echo grep sed sleep tail
Tags: bash sed curl osx

Instead of having someone else read you the Digg headlines, Have OSX do it. Requires Curl+Sed+Say. This could probably be easily modified to use espeak for Linux.

$COMMAND 2>&1 >/dev/null & WPID=$!; sleep $TIMEOUT && kill $! & KPID=$!; wait $WPID
2010-05-26 11:12:26
User: keymon
Functions: kill sleep wait

I like much more the perl solution, but without using perl. It launches a backgroup process that will kill the command if it lasts too much.

A bigger function:

check_with_timeout() {

[ "$DEBUG" ] && set -x




# Launch command in backgroup

[ ! "$DEBUG" ] && exec 6>&2 # Link file descriptor #6 with stderr.

[ ! "$DEBUG" ] && exec 2> /dev/null # Send stderr to null (avoid the Terminated messages)

$COMMAND 2>&1 >/dev/null &


[ "$DEBUG" ] && echo "Background command pid $COMMAND_PID, parent pid $$"

# Timer that will kill the command if timesout

sleep $TIMEOUT && ps -p $COMMAND_PID -o pid,ppid |grep $$ | awk '{print $1}' | xargs kill &


[ "$DEBUG" ] && echo "Killer command pid $KILLER_PID, parent pid $$"



# Kill the killer timer

[ "$DEBUG" ] && ps -e -o pid,ppid |grep $KILLER_PID | awk '{print $1}' | xargs echo "Killing processes: "

ps -e -o pid,ppid |grep -v PID | grep $KILLER_PID | awk '{print $1}' | xargs kill


sleep 1

[ ! "$DEBUG" ] && exec 2>&6 6>&- # Restore stderr and close file descriptor #6.

return $RET


tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log
2010-04-29 21:23:46
User: dooblem
Functions: kill sleep tail wc
Tags: tail kill wc sleep

Another way of counting the line output of tail over 10s not requiring pv.

Cut to have the average per second rate :

tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2

You can also enclose it in a loop and send stderr to /dev/null :

while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

very_long_command& sleep 10; kill $!
2010-04-29 20:43:13
User: dooblem
Functions: kill sleep

or "Execute a command with a timeout"

Run a command in background, sleep 10 seconds, kill it.

! is the process id of the most recently executed background command.

You can test it with:

find /& sleep10; kill $!

mv ubuntu-10.04-rc-desktop-amd64.iso ubuntu-10.04-desktop-amd64.iso; i=http://releases.ubuntu.com/10.04/ubuntu-10.04-desktop-amd64.iso.zsync; while true; do if wget $i; then zsync $i; date; break; else sleep 30; fi; done
2010-04-29 15:49:43
Functions: mv sleep wget

Need to have rc iso pre-downloaded before running command.

while true; do if wget http://releases.ubuntu.com/10.04/ubuntu-10.04-desktop-i386.iso.torrent; then ktorrent --silent ubuntu-10.04-desktop-i386.iso.torrent ; date; break; else sleep 5m; fi; done
2010-04-29 13:22:54
User: ppaschka
Functions: sleep wget

Tested with 9.10 release. Choose whatever torrent client you prefer.

diff <(lsof -p 1234) <(sleep 10; lsof -p 1234)
2010-03-15 22:55:32
User: zlemini
Functions: diff sleep

This command takes a snapshot of the open files for a PID 1234 then waits 10 seconds and takes another snapshot of the same PID, it then displays the difference between each snapshot to give you an insight into what the application is doing.

while true; do xdotool getmouselocation | sed 's/x:\(.*\) y:\(.*\) screen:.*/\1, \2/' >> ./mouse-tracking; sleep 10; done
2010-02-27 04:00:13
User: matthewbauer
Functions: sed sleep

Will track your mouse and save it to a file.

You can use gnuplot to graph it:

gnuplot -persist <(echo "unset key;unset border;unset yzeroaxis;unset xtics;unset ytics;unset ztics;plot './mouse-tracking' with points lt 1 pt 6 ps variable")
echo "Starting Daemon"; ( while :; do sleep 15; echo "I am still running =]"; done ) & disown -h $!
2010-02-23 19:17:05
User: daleki
Functions: echo sleep

You don't want the -ar parameters in this case. The man page for BASH_BUILTINS(1) states:

"-a option means to remove or mark all jobs" and

"-r option without a jobspec argument restricts operation to running jobs"

In this case we are supplying the process id of the job to disown so neither of these should be used.

sleep 3 && xdotool type --delay 0ms texthere
2010-02-18 11:44:18
User: drinkcat
Functions: sleep type
Tags: Linux

Just after you type enter, you have 3 seconds to switch window, then "texthere" will be "typed" in the X11 application that has focus. Very useful to beat your score at games such as "How fast can you type A-Z".

while true; do xvkbd -xsendevent -text "\[$KEY]" && sleep 2; done
2010-01-28 03:11:10
User: matthewbauer
Functions: sleep

Press a key automatically via xvkbd.

podwebserver& sleep 2; elinks ''
2010-01-27 10:57:34
User: vlan7
Functions: sleep

Prerequisites: module Pod::Webserver installed. You can install it typing:

sudo perl -MCPAN -e 'install Pod::Webserver'

You can replace elinks with your fav browser. For FF:

podwebserver& sleep 2; firefox -remote 'openurl(, new-tab )'

If you have Firefox open, this will pop-up the index web in a new tab.

(IFS=; sed 's/^[]0;[^^G]*^G/^M/g' <SessionLog> | while read -n 1 ITEM; do [ "$ITEM" = "^M" ] && ITEM=$'\n'; echo -ne "$ITEM"; sleep 0.05; done; echo)
2010-01-20 16:11:32
User: jgc
Functions: echo read sed sleep
Tags: read script

This command will play back each keystroke in a session log recorded using the script command. You'll need to replace the ^[ ^G and ^M characters with CTRL-[, CTRL-G and CTRL-M. To do this you need to press CTRL-V CTRL-[ or CTRL-V CTRL-G or CTRL-V CTRL-M.

You can adjust the playback typing speed by modifying the sleep.

If you're not bothered about seeing each keypress then you could just use:

cat session.log
while (ps -ef | grep [r]unning_program_name); do sleep 10; done; command_to_execute
2010-01-14 16:26:34
User: m_a_xim
Functions: grep ps sleep

The '[r]' is to avoid grep from grepping itself. (interchange 'r' by the appropriate letter)

Here is an example that I use a lot (as root or halt will not work):

while (ps -ef | grep [w]get); do sleep 10; done; sleep 60; halt

I add the 'sleep 60' command just in case something went wrong; so that I have time to cancel.

Very useful if you are going to bed while downloading something and do not want your computer running all night.

dd if=fromfile of=tofile & DDPID=$! ; sleep 1 ; while kill -USR1 $DDPID ; do sleep 5; done
2010-01-12 15:01:44
User: deltaray
Functions: dd kill sleep
Tags: dd kill while sleep

This is a more accurate way to watch the progress of a dd process. The $DDPID=$! is needed so that you don't get the PID of the sleep. The sleep 1 is needed because in my testing at least, if you run kill -USR1 against dd too quickly, it will kill it off instead of display the status. So you need to wait a second, probably so that it can configure itself to trap the USR1 signal.

dd if=/dev/sdc of=/dev/sdd conv=notrunc & while killall -USR1 dd; do sleep 5; done
2010-01-12 14:09:40
User: bw
Functions: dd killall sleep

The following command will clone usb stick inside /dev/sdc to /dev/sdd

Double check you got the correct usb sticks (origional-clone)with fdisk -l.

p(){ printf "\033[%d;%dH\033[4%dm \033[m" $((RANDOM%LINES+1)) $((RANDOM%COLUMNS+1)) $((RANDOM%8)); }; clear;while :;do p; sleep .001;done