Commands using echo (1,388)

  • Usage example: newest Desktop/* Replace "-nt" with "-ot" for oldest. Run shopt -s dotglob first to include dotfiles.


    1
    newest () { candidate=''; for i in "$@"; do [[ -f $i ]] || continue; [[ -z $candidate || $i -nt $candidate ]] && candidate="$i"; done; echo "$candidate"; }
    johnraff · 2009-10-29 17:35:01 0
  • bash2 : for X in $(seq 1 5); do printf "%03g " "$X";done bash3 : for X in {1..5}; do printf "%03g " "$X";done bash4 : echo {001..5} Show Sample Output


    6
    echo {001..5}
    nanard06 · 2009-10-29 16:25:44 3
  • If you receives a lot of compiling errors, type 'clear', then reedit your code and press "SHIFT+PGUP". Show Sample Output


    -3
    alias clear='( for ((i=1;i<$LINES;i++)) ; do echo "" ; done ) ; clear'
    Marcio · 2009-10-27 14:38:31 0
  • If a command returns a error code, you will know Show Sample Output


    0
    export PROMPT_COMMAND='( x=$? ; let x!=0 && echo shell returned $x )'
    Marcio · 2009-10-27 14:27:55 1
  • make password randomly, default 8 char


    -1
    genpass() { local h x y;h=${1:-8};x=( {a..z} {A..Z} {0..9} );y=$(echo ${x[@]} | tr ' ' '\n' | shuf -n$h | xargs);echo -e "${y// /}"; }
    twfcc · 2009-10-24 04:05:42 0
  • Alternative to the ping check if your firewall blocks ping. Uses curl to get the landing page silently, or fail with an error code. You can probably do this with wget as well. Show Sample Output


    2
    curl -fs brandx.jp.sme 2&>1 > /dev/null || echo brandx.jp.sme ping failed | mail -ne -s'Server unavailable' joker@jp.co.uk
    mccalni · 2009-10-23 14:29:06 0
  • Strip my code to: wmctrl -o 0,0 # autorotates to the first face. In fact [0-1279],0 wmctrl - 1280,0 # goes to the second face wmctrl -o 2560,0 # goes to the third face, and so on. # Use multiples of the horizontal display resolution. My example work for 1280x800 display, been 1280 the number of interest. Tweak the number, try a biiiig one and see your cube spinning... I put a complex example to show how fun things can be, even for my ademco and paradox alarm central network advisor interface xpto etc. It rotates two faces, print the alarm message, and goes back tho where it was. Tested on BIGLINUX 4.2, equivalent to ubuntu LTS hardy. Do not forget to activate 3D efects ( compiz cube ) Show Sample Output


    5
    wmctrl -o 2560,0 ;sleep 2 ; echo "FIRE 001" | osd_cat -o 470 -s 8 -c red -d 10 -f -*-bitstream\ vera\ sans-*-*-*--250-*-*-*-*-*-*-* ; sleep 1; wmctrl -o 0,0
    m33600 · 2009-10-23 10:00:51 0
  • already described on the other two versions, this one uses ascii characters on game style to display elapsed time. Show Sample Output


    0
    export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | toilet -f shadow'
    m33600 · 2009-10-23 07:56:30 0
  • Variation of the theme, this one blinks in low profile on top level of X, ie, it is visible, indeed small. Try changing fonts and sizes of osd_cat


    0
    export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | osd_cat -o 20 -d 1 -p bottom'
    m33600 · 2009-10-23 07:47:11 0
  • Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch Shows elapsed time from start of script in hh:mm:ss format Non afected by system slow down due to the use of date.


    3
    export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds)'
    m33600 · 2009-10-23 07:31:44 1
  • Can easily be scripted in order to show permission "tree" from any folder. Can also be formated with column -t { pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null ; } | column -t from http://www.commandlinefu.com/commands/view/3731/using-column-to-format-a-directory-listing Show Sample Output


    0
    pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null
    syladmin · 2009-10-22 12:32:11 0

  • 7
    echo $(shuf -i 1-49 | head -n6 | sort -n)
    twfcc · 2009-10-22 06:48:20 0

  • 0
    seg() { for b in $(echo $1); do for x in $(seq 10); do echo $b.$x; done; done }
    Waldirio · 2009-10-20 18:14:25 0

  • 0
    seg() { echo -e "$1" | while read LINE; do for b in $(seq 10); do echo $LINE.$b; done; done; }
    Waldirio · 2009-10-20 17:45:43 0
  • This is a bit hacky, but if you're setting up a bunch of new LUNs, it can save a bunch of time. Also check out sfdisk. The fdisk will fail if, for example, a partition table already exists.


    -1
    echo -e "n\np\n1\n\n\nt\n8e\nw" | fdisk /dev/sdX
    sud0er · 2009-10-20 16:21:54 0
  • See: http://imgur.com/JgjK2.png for example. Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1). Run: gnuplot -persist <(echo "plot 'lzma' with lines, 'gzip' with lines, 'bzip2' with lines") To see it in graph form.


    3
    for a in bzip2 lzma gzip;do echo -n>$a;for b in $(seq 0 256);do dd if=/dev/zero of=$b.zero bs=$b count=1;c=$(date +%s%N);$a $b.zero;d=$(date +%s%N);total=$(echo $d-$c|bc);echo $total>>$a;rm $b.zero *.bz2 *.lzma *.gz;done;done
    matthewbauer · 2009-10-20 01:00:51 2
  • This time I added a print to reemaining energy, every minute, time stamped. The example shown here is complete and point to large discrepancies as time passes, converging to accuracy near the end. Show Sample Output


    1
    echo start > battery.txt; watch -n 60 'date >> battery.txt ; acpi -b >> battery.txt'
    m33600 · 2009-10-19 05:28:15 0
  • Fully recharge your computer battery and start this script. It will create or clean the file named battery.txt, print a start on it and every minute it will append a time stamp to it. Batteries last few hours, and each hour will have 60 lines of time stamping. Really good for assuring the system was tested in real life with no surprises. The last time stamp inside the battery.txt file is of interest. It is the time the computer went off, as the battery was dead! Turn on your computer after that, on AC power of course, and open battery.txt. Read the first and last time stamps and now you really know if you can trust your computer sensors. If you want a simple line of text inside the battery.txt file, use this: watch -n 60 'date > battery.txt' The time of death will be printed inside Show Sample Output


    0
    echo start > battery.txt; watch -n 60 'date >> battery.txt'
    m33600 · 2009-10-18 07:00:26 0
  • the shortest command for character 'a' i know Show Sample Output


    1
    echo -n a | od -d | sed -n "s/^.* //gp"
    stf42 · 2009-10-17 15:46:00 0
  • Doesn't fail for percent sign now.


    0
    chr () { echo -en "\0$(printf %x $1)"}
    infinull · 2009-10-16 21:54:58 1
  • uses the previous "chr" function and uses it to create the inverse function "ord" by brute force. It's slow, It's inelegant, but it works. I thought I needed ord/chr to do a cartesian cipher in shell script a whie ago, but eventualy I realized I could get fancy with tr and do the same thing...


    0
    ord () { seq 1 127 | while read i; do echo `chr $i` $i; done | grep "^$1 " | cut -c '3-' }
    infinull · 2009-10-16 21:54:01 1

  • -4
    echo "" > .bash_history
    osvaldofilho · 2009-10-16 12:55:53 0
  • Email if you disk is over 90% - www.fir3net.com


    -1
    HDD=$(df | awk ' NR>3 (S=$5) (M=$6) { if (S>90) print "Your Systems "M" is """S" Full" } ') ; [[ $HDD ]] && echo "$HDD" | mail -s "Hard-Drives Full" TO@EMAIL.com -- -f FROM@EMAIL.com >/dev/null
    felix001 · 2009-10-16 06:52:36 2
  • Nice command to create a list, you can create too with for command, but this is so faster. Show Sample Output


    0
    seq 10 |xargs -n1 echo Printing line
    Waldirio · 2009-10-15 11:05:35 0

  • -2
    n=$RANDOM$RANDOM$RANDOM; let "n %= 10000000000"; echo $n
    alset · 2009-10-15 05:10:00 1
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