Commands using sleep (289)

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


    2
    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; }
    aguslr · 2014-11-26 10:22:18 7
  • 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.


    2
    while [ "$(ls -l --full-time TargetFile)" != "$a" ] ; do a=$(ls -l --full-time TargetFile); sleep 10; done
    dmmst19 · 2015-05-09 03:19:49 11

  • 2
    while true; do date; ps auxf | awk '{if($8=="D") print $0;}'; sleep 1; done
    tictacbum · 2015-09-19 07:23:32 11
  • 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) Show Sample Output


    2
    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
    BeniBela · 2015-09-23 23:00:14 24
  • (In French) Connection aux hotspots FreeWifi, et maintien de la connection active


    2
    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
    pascalvaucheret · 2016-07-23 16:34:42 15
  • 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 me+trash@gmail.com can be filtered with "Matches: DeliveredTo:me+trash@gmail.com" Show Sample Output


    2
    while true ; do fswebcam -d /dev/video0 -r 1280x1024 -F 15 - | uuencode $(date +\%Y\%m\%d\%H\%M).jpeg | mail -s "Video surveillance" $USER ; sleep 300 ; done
    pascalvaucheret · 2016-08-09 14:22:45 14
  • This will ring the system bell once if your script exits successfully and twice if it fails. So you can go look at something else and it will alert you when done. Don't forget to use 'xset b [vol [pitch [duration]]]' to get the bell to sound the way you want.


    1
    myLongScript && echo -e '\a' || (echo -e '\a'; sleep 1; echo -e '\a')
    stuart · 2009-02-05 22:13:43 18

  • 1
    f="FILE";c="CMD";s="stat -f %m $f";t=`$s`;while [ 1 ];do if [ $t -eq `$s` ];then sleep 1;else echo `$c`;t=`$s`;fi;done
    yanbe · 2009-02-06 03:04:39 22
  • wrapping the snippet in $( )& puts the whole thing in the background so you don't tie up your login session.


    1
    $(STEEP=300; sleep $STEEP; xmessage "Your tea is done") &
    sud0er · 2009-02-19 20:10:49 5
  • The variable WIRELESSINTERFACE indicates your wireless interface


    1
    while [ i != 0 ]; do sleep 1 | dialog --clear --gauge "Quality: " 0 0 $(cat /proc/net/wireless | grep $WIRELESSINTERFACE | awk '{print $3}' | tr -d "."); done
    ncaio · 2009-05-31 16:09:23 12
  • checkfor: have the shell check anything you're waiting for. 'while : ; do' is an infinite loop '$*' executes the command passed in 'sleep 5' - change for your tastes, sleep for 5 seconds bash, ksh, likely sh, maybe zsh Ctrl-c to break the loop Show Sample Output


    1
    function checkfor () { while :; do $*; sleep 5; done; }
    relay · 2009-09-03 19:35:42 6
  • [Note: This command needs to be run as root]. If you are downloading something large at night, you can start wget as a normal user and issue the above command as root. When the download is done, the computer will automatically go to sleep. If at any time you feel the computer should not go to sleep automatically(like if you find the download still continuing in the morning), just create an empty file called nosleep in /tmp directory.


    1
    while [ -n "`pgrep wget`" ]; do sleep 2 ;done; [ -e "/tmp/nosleep"] || echo mem >/sys/power/state
    kamathln · 2009-09-06 05:51:20 3
  • Get sopcast links for live sports from http://myp2p.eu (for example) Get sp-sc or sp-auth binary by googling (sopcast + linux) eg http://www.jbg.f2s.com/sp-sc.gz Requires the 32bit libstdc++5 package. After exiting mplayer, type 'killall sp-sc'


    1
    (sp-sc sop://broker.sopcast.com:3912/6002 3900 8900 &>/dev/null &); sleep 10; mplayer http://localhost:8900/tv.asf
    Escher · 2009-09-19 17:46:13 16
  • If the remote doesn't export its desktop (eg fluxbox, blackbox etc) then you need to run a x11vnc server there and a vncviewer at the local end. This command does the lot for you - it assumes that you can 'ssh' to the box without a password and that x11vnc is installed at the remote end.


    1
    rdp() { ssh $1 sh -c 'PATH=$PATH:/usr/local/bin; x11vnc -q -rfbauth ~/.vnc/passwd -display :0' & sleep 4; vncviewer $1:0 & }
    bhepple · 2009-11-25 07:21:02 3
  • This command can be set as an alias in ~/.bashrc For example (in my case) I have : alias watchDl='while [ "$(ls $filePart)" != "" ]; do sleep 5; done; mpg123 /home/.../warning.mp3" ' Then I just need to - initialize filePart (e.g. filePart="*bigFile*rar.part") - launch watchDl


    1
    while [ "$(ls $filePart)" != "" ]; do sleep 5; done; mpg123 /home/.../warning.mp3
    mrttlemonde · 2009-12-06 10:55:09 9
  • Press a key automatically via xvkbd.


    1
    while true; do xvkbd -xsendevent -text "\[$KEY]" && sleep 2; done
    matthewbauer · 2010-01-28 03:11:10 14
  • Tested with 9.10 release. Choose whatever torrent client you prefer.


    1
    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
    ppaschka · 2010-04-29 13:22:54 7
  • 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


    1
    tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log
    dooblem · 2010-04-29 21:23:46 16
  • Requires figlet. Other than that, this should be portable enough across all the Bourne-compatible shells (sh, bash, ksh, zsh, etc). Produces a massive number using figlet that counts down the number of seconds for any given minute interval. For example, here's a 4-minute timer: i=$((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; Show Sample Output


    1
    i=$((15*60)); while [ $i -gt 0 ]; do clear; echo $i | figlet; sleep 1; i=$(($i-1)); done;
    atoponce · 2010-06-22 17:49:36 5
  • 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?


    1
    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!"; }
    kniht · 2010-06-30 12:20:01 5
  • very handy if you copy or download a/some file(s) and want to know how big it is at the moment


    1
    while true; do du -s <file_or_directory>; sleep <time_interval>; done
    potatoface · 2010-08-24 19:55:13 3
  • This is like ping -a, but it does the opposite. It alerts you if the network is down, not up. Note that the beep will be from the speaker on the server, not from your terminal. Once a second, this script checks if the Internet is accessible and beeps if it is not. I define the Net as being "UP", if I can ping Google's public DNS server (8.8.8.8), but of course you could pick a different static IP address. I redirect the beep to /dev/console so that I can run this in the background from /etc/rc.local. Of course, doing that requires that the script is run by a UID or GID that has write permissions to /dev/console (usually only root). Question: I am not sure if the -W1 flag works under BSD. I have only tested this under GNU/Linux using ping from iputils. If anybody knows how portable -W is, please post a comment.


    1
    while :; do ping -W1 -c1 -n 8.8.8.8 > /dev/null || tput bel > /dev/console; sleep 1; done
    hackerb9 · 2010-09-24 06:34:12 7
  • No need for a colon, and one less semicolon too. Also untested.


    1
    while sleep 1; do acpi -t | osd_cat -p bottom; done &
    linuts · 2011-01-14 23:22:57 4
  • Mutes the speakers after an hour, in case you fall asleep watching a video...


    1
    sleep 3600; amixer set Master mute
    kenbarbour · 2011-02-06 03:14:33 6

  • 1
    pkill -0 prog1; while [ $? -eq 0 ]; do sleep 10; pkill -0 prog1; done; prog2
    Saorel · 2011-02-11 21:46:42 10
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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

cpuinfo

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

floating point operations in shell scripts
allows you to use floating point operations in shell scripts

Given process ID print its environment variables
Same as previous but without fugly sed =x

Double your disk read performance in a single command
(WARN) This will absolutely not work on all systems, unless you're running large, high speed, hardware RAID arrays. For example, systems using Dell PERC 5/i SAS/SATA arrays. If you have a hardware RAID array, try it. It certainly wont hurt. You may be can test the speed disk with some large file in your system, before and after using this: $ time dd if=/tmp/disk.iso of=/dev/null bs=256k To know the value of block device parameter known as readahead. $ blockdev --getra /dev/sdb And set the a value 1024, 2048, 4096, 8192, and maybe 16384... it really depends on the number of hard disks, their speed, your RAID controller, etc. (see sample)

Shell function to create a menu of items which may be inserted into the X paste buffer.
The function will take a comma separated list of items to be 'selected' by xsel -i: $ smenu "First item to paste,Paste me #2,Third menu item" You will then be prompted to choose one of the menu items. After you choose, you will be able to paste the string by clicking the middle mouse button. The menu will keep prompting you to choose menu items until you break out with Control-C.

Make changes in any profile available immediately/Change to default group
Changes your group to the default group, has the same effect as sourcing your profile/rc file (in any shell) or logging out and back in again.

FAST Search and Replace for Strings in all Files in Directory
I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.

exit if another instance is running


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