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May 19, 2015 - A Look At The New Commandlinefu
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Commands tagged sleep from sorted by
Terminal - Commands tagged sleep - 33 results
echo FileName | perl -nlE'sleep 1 while time-(stat)[10]<10' && echo DONE
2015-05-09 14:58:41
User: pung96
Functions: echo perl

perl version of "Wait for file to stop changing"

When "FileName" has not been changed for last 10 seconds, then print "DONE"

"10" in "(stat)[10]" means ctime.

One have other options like atime, mtime and others. http://perldoc.perl.org/functions/stat.html

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

A nice way to interrupt a sleep with a signal.

bkname="test"; tobk="*" ; totalsize=$(du -csb $tobk | tail -1 | cut -f1) ; tar cvf - $tobk | tee >(sha512sum > $bkname.sha512) >(tar -tv > $bkname.lst) | mbuffer -m 4G -P 100% | pv -s $totalsize -w 100 | dd of=/dev/nst0 bs=256k
2014-07-22 15:47:50
User: johnr
Functions: cut dd du tail tar tee

This will write to TAPE (LTO3-4 in my case) a backup of files/folders. Could be changed to write to DVD/Blueray.

Go to the directory where you want to write the output files : cd /bklogs

Enter a name in bkname="Backup1", enter folders/files in tobk="/home /var/www".

It will create a tar and write it to the tape drive on /dev/nst0.

In the process, it will

1) generate a sha512 sum of the tar to $bkname.sha512; so you can validate that your data is intact

2) generate a filelist of the content of the tar with filesize to $bkname.lst

3) buffer the tar file to prevent shoe-shining the tape (I use 4GB for lto3(80mb/sec), 8gb for lto4 (120mb/sec), 3Tb usb3 disks support those speed, else I use 3x2tb raidz.

4) show buffer in/out speed and used space in the buffer

5) show progress bar with time approximation using pv


To eject the tape :

; sleep 75; mt-st -f /dev/nst0 rewoffl


1) When using old tapes, if the buffer is full and the drive slows down, it means the tape is old and would need to be replaced instead of wiping it and recycling it for an other backup. Logging where and when it slows down could provide good information on the wear of the tape. I don't know how to get that information from the mbuffer output and to trigger a "This tape slowed down X times at Y1gb, Y2gb, Y3gb down to Zmb/s for a total of 30sec. It would be wise to replace this tape next time you want to write to it."

2) Fix filesize approximation

3) Save all the output to $bkname.log with progress update being new lines. (any one have an idea?)

4) Support spanning on multiple tape.

5) Replace tar format with something else (dar?); looking at xar right now (https://code.google.com/p/xar/), xml metadata could contain per file checksum, compression algorithm (bzip2, xv, gzip), gnupg encryption, thumbnail, videopreview, image EXIF... But that's an other project.


1) You can specify the width of the progressbar of pv. If its longer than the terminal, line refresh will be written to new lines. That way you can see if there was speed slowdown during writing.

2) Remove the v in tar argument cvf to prevent listing all files added to the archive.

3) You can get tarsum (http://www.guyrutenberg.com/2009/04/29/tarsum-02-a-read-only-version-of-tarsum/)

and add >(tarsum --checksum sha256 > $bkname_list.sha256) after the tee to generate checksums of individual files !

while true; do clear;awk '{a[$3]+=1};END{for(x in a){print x,a[x]}}' /proc/[0-9]*/stat; sleep 1; done
sysctl kern.sleeptime
sysctl kern.sleeptime
sysctl -a | grep sleeptime
2013-07-29 07:57:01
User: themiurgo
Functions: grep sysctl
Tags: sleep mac os x

Similarly for last wake time:

sysctl -a | grep waketime
while curl -dsL example.com 2>&1 | grep 503;do sleep 8;done;echo server up
while true; do curl -vsL -o /dev/null example.com 2>&1 | grep 503 > /dev/null || echo "OK: server is up."; sleep 8; done
pmi action suspend
sleep $((3600 - ($(date +%s) % 3600) ))
2012-12-09 16:21:57
User: Mozai
Functions: date sleep

pauses exactly long enough to wake at the top of the hour

for host in $HOSTNAMES; do ping -q -c3 $host && ssh $host 'command' & for count in {1..15}; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done &>/dev/null
for host in $MYHOSTS; do ping -q -c3 $H 2>&1 1>/dev/null && ssh -o 'AllowedAuthe ntications publickey' $host 'command1; command2' & for count in 1 2 3 4 5; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done
2012-11-13 23:12:27
User: a8ksh4
Functions: grep host jobs kill ping sleep ssh wc

Execute commands serially on a list of hosts. Each ssh connection is made in the background so that if, after five seconds, it hasn't closed, it will be killed and the script will go on to the next system.

Maybe there's an easier way to set a timeout in the ssh options...

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.

sleep 3;import -window root output.png
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

echo mem|sudo tee /sys/power/state
delay until 16 && import_db.sh
2012-03-01 12:38:32
User: oernii2

the "delay" utility is an invaluable tool for me. with gnu-screen it allows you to schedule something and have it run and output to the current terminal, unlike "at".

You can also use it like "sleep" with seconds and also with date:

delay until 13:33 friday && echo test

get it from: http://onegeek.org/~tom/software/delay/current/delay.c

(author: Tom Rothamel)

for line in `cat $file`; do firefox -new-tab "$line" & 2>/dev/null; sleep 1; done
2011-11-12 13:47:24
User: hamsolo474
Functions: sleep

this will open a new tab in firefox for every line in a file

the sleep is removable but i found that if you have a large list of urls 50+, and no sleep, it will try to open all the urls at once and this will cause them all to load a lot slower, also depending on the ram of your system sleep gives you a chance to close the tabs before they overload your ram, removing & >2/dev/null will yield unpredictable results.

MIN=10;for ((i=MIN*60;i>=0;i--));do echo -ne "\r$(date -d"0+$i sec" +%H:%M:%S)";sleep 1;done
2011-02-20 11:56:28
User: flatcap
Functions: echo sleep

Countdown clock - Counts down from $MIN minutes to zero.

I let the date command do the maths.

This version doesn't use seq.

cycle(){ while :;do((i++));echo -n "${3:$(($i%${#3})):1}";sleep .$(($RANDOM%$2+$1));done;}
2010-10-08 23:45:40
User: putnamhill
Functions: echo sleep
Tags: sleep random

Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption.

cycle 1 3 $(openssl rand 100 | xxd -p)

Fans of "The Shining" might get a kick out of this:

cycle 1 4 ' All work and no play makes Jack a dull boy.'
dbus-send --system --print-reply --dest=org.freedesktop.UPower /org/freedesktop/UPower org.freedesktop.UPower.Suspend
2010-08-05 00:16:40
User: ianux
Tags: sleep suspend

No need to be root to do that. Relies on UPower (previously known as DeviceKit-Power).

sudo pm-suspend
sudo /etc/acpi/sleep.sh sleep
2010-08-03 23:54:49
User: jmfork
Functions: sudo
Tags: sleep suspend

It suspends to RAM: you always need your batteries for the RAM but it saves time as there is no need to slowly archive everything on your hard disk.

It works fine with me but if anyone has a nicer way, please contribute.