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Commands using echo from sorted by
Terminal - Commands using echo - 1,316 results
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
2015-09-23 23:00:14
User: BeniBela
Functions: cut date echo grep sleep
1

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)

echo apt-get\ {update,-y\ upgrade}\ \&\& true | sudo bash
2015-09-22 00:48:26
User: alecthegeek
Functions: echo sudo true
1

it's nice to be able to use the command `ls program.{h,c,cpp}`. This expands to `ls program.h program.c program.cpp`. Note: This is a text expansion, not a shell wildcard type expansion that looks at matching file names to calculate the expansion. More details at http://www.linuxjournal.com/content/bash-brace-expansion

I often run multiple commands (like apt-get) one after the other with different subcommands. Just for fun this wraps the whole thing into a single line that uses brace expansion.

[ $(date +"%H") -lt 7 ] && echo you should probably be sleeping...
btc() { echo "1 BTC = $(curl -s https://api.coindesk.com/v1/bpi/currentprice/$1.json | jq .bpi.\"$1\".rate | tr -d \"\"\") $1"; }
2015-09-19 02:49:30
User: benjabean1
Functions: echo
-1

The only pre-requisite is jq (and curl, obviously).

The other version used grep, but jq is much more suited to JSON parsing than that.

echo "1 BTC = $(curl -s https://api.coindesk.com/v1/bpi/currentprice/usd.json | grep -o 'rate":"[^"]*' | cut -d\" -f3) USD"
echo "quit" | openssl s_client -connect facebook.com:443 | openssl x509 -noout -text | grep "DNS:" | perl -pe "s/(, )?DNS:/\n/g"
ran() { R=$((RANDOM%100)); if [ $R -gt "${1:-50}" ]; then echo FALSE; false; else echo TRUE; true; fi; }
2015-07-15 15:34:56
User: snipertyler
Functions: echo
0

Command will succeed n% of the time.

ran 75 will cause command to succeed 75% of the time.

No argument will cause it to succeed 50% of the time.

echo "text to prepend" | cat - file
for file in $( git ls-files ); do echo $file; touch -t $(git --no-pager log --date=local -1 --format="%ct" $file | php -r 'echo @date( "YmdHi.s", trim( file_get_contents( "php://stdin" ) ) );') $file; done
echo "display:data?" | nc "$scope_ip_address" 5555 | dd bs=1 skip=11 2>/dev/null | convert bmp:- out_file.png
2015-06-27 06:43:43
User: ichbins
Functions: dd echo
Tags: convert rigol
1

Scope should have the Rigol Ultravision Technology otherwise it won't accept the command. ImageMagic is required. Scope sends a 1.1M BMP file and converted to PNG it's only 18-20K

for x in {a..d}; do echo -e "n\np\n\n\n\nt\n8e\nw\n" | fdisk /dev/sd"$x"; done
2015-05-21 12:59:48
User: jaimerosario
Functions: echo fdisk
Tags: fdisk for loop
1

So, I'm using a CentOS VM in VirtualBox, and created four new disks in the SCSI controller.

The VM created the folders:

/dev/sda

/dev/sdb

/dev/sdc

/dev/sdd

Using a 'for loop' all disks are partitioned for LVM.

for p in $(pgrep -t $(cat /sys/class/tty/tty0/active)); do d=$(awk -v RS='\0' -F= '$1=="DISPLAY" {print $2}' /proc/$p/environ 2>/dev/null); [[ -n $d ]] && break; done; echo $d
2015-05-18 20:01:20
User: geyslan
Functions: awk cat echo
Tags: display xorg
1

It's useful when you cannot access your env (systemd) or the process DISPLAY variable is not set. Perhaps also when you have a multi-head/user configuration.

fileinfo() { RPMQF=$(rpm -qf $1); RPMQL=$(rpm -ql $RPMQF);echo "man page:";whatis $(basename $1); echo "Services:"; echo -e "$RPMQL\n"|grep -P "\.service";echo "Config files:";rpm -qc $RPMQF;echo "Provided by:" $RPMQF; }
2015-05-11 16:46:01
User: nnsense
Functions: basename echo grep rpm whatis
2

Many times I give the same commands in loop to find informations about a file. I use this as an alias to summarize that informations in a single command. Now with variables! :D

echo FileName | perl -nlE'sleep 1 while time-(stat)[10]<10' && echo DONE
2015-05-09 14:58:41
User: pung96
Functions: echo perl
0

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
3

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.

echo $(date +%m) past $(date +%H) | espeak
2015-05-09 12:24:13
User: hal8
Functions: date echo
0

s/espeak/say/ on a mac

echo -e $_{1..80}'\b+'
while kill -0 0; do timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for _ in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'; done
2015-05-07 19:13:08
User: anapsix
Functions: bash echo kill seq sleep
2

alternatively, run the spinner for 5 seconds:

timeout 5 bash -c 'spinner=( Ooooo oOooo ooOoo oooOo ooooO oooOo ooOoo oOooo); while true; do for i in ${spinner[@]}; do for j in seq 0 ${#i}; do echo -en "\b\b"; done; echo -ne "${i}"; sleep 0.2; done; done'

echo -e ''$_{1..80}'\b+'
2015-05-05 22:13:33
User: knoppix5
Functions: echo
3

(here is character '+' repeated 80 times)

Sometimes needed to enhance the title of the script.

clear; while sleep 1; do d=$(date +"%H:%M:%S"); e=$(echo "toilet -t -f mono12 $d");tput setaf 1 cup 0; eval $e; tput setaf 4 cup 8; eval "$e -F flop";tput cup 0; done
function summaryIP() { < $1 awk '{print $1}' | while read ip ; do verifyIP ${ip} && echo ${ip}; done | awk '{ip_array[$1]++} END { for (ip in ip_array) printf("%5d\t%s\n", ip_array[ip], ip)}' | sort -rn; }
2015-05-01 16:45:05
User: mpb
Functions: awk echo read sort
1

Working with lists of IP addresses it is sometimes useful to summarize a count of how many times an IP address appears in the file.

This example, summarizeIP, uses another function "verifyIP" previously defined in commandlinefu.com to ensure only valid IP addresses get counted. The summary list is presented in count order starting with highest count.

echo "DISPLAY=$DISPLAY xmessage call the client" | at 10:00
2015-05-01 14:57:15
User: op4
Functions: at echo
Tags: echo at xmessage
2

This command will create a popup reminder window to assist in remembering tasks

http://i.imgur.com/2n7viiA.png is how it looks when created

test "$(md5sum /local/file | cut -d' ' -f1)" == "$(ssh [email protected] -- md5sum /remote/file | cut -d' ' -f1)" && echo "Match" || echo "Differ"
2015-04-24 03:09:33
User: gnif
Functions: echo test
1

This method does not transfer the contents of the entire file, instead it computes a md5 sum of the file on each end so that large files can be compared without transferring them across the net.

fold -sw 20 <(echo "Long Text to be wrapped with \"\n\"") |sed ':a;N;$!ba;s/ *\n/\\n/g'
2015-04-16 21:06:53
User: alecthegeek
Functions: echo fold sed
1

I used this fragment with Imagemagick convert so that I can place long text strings in pictures. The "\n" gets converted to a true newline in the image.

So this fragment uses fold command to wrap the line and then sed to convert newlines (and any trailing spaces on the line) to the text "\n"

find /PATHNAME -type l | while read nullsymlink ; do wrongpath=$(readlink "$nullsymlink") ; right=$(echo "$wrongpath" | sed s'|OLD_STRING|NEW_STRING|') ; ln -fs "$right" "$nullsymlink" ; done
2015-04-14 14:58:41
User: iDudo
Functions: echo find ln read readlink sed
1

After you run this script, you can check status for broken symlink with this command:

find -L . -type l