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Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using echo from sorted by
Terminal - Commands using echo - 1,317 results
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

awk '{print $0+0}' <(echo -2; echo +3;)
2015-04-08 09:19:24
Functions: awk echo
0

The leading plus sign is removed - Minus sign is left intact

a=$(b=$(($LINES/2));f() { for c in $(seq $b); do for i in $(seq $c);do echo x;done|xargs echo;done };paste <(f) <(f|tac|tr 'x' '-') <(f|tac|tr 'x' '-') <(f)|tr '\t' ' ');(cat <<<"$a"|tac;cat <<<"$a")|tr '-' ' '
crontest () { date +'%M %k %d %m *' |awk 'BEGIN {ORS="\t"} {print $1+2,$2,$3,$4,$5,$6}'; echo $1;}
2015-03-12 19:56:56
User: CoolHand
Functions: awk date echo
0

usage = crontest "/path/to/bin"

This version of this function will echo back the entire command so it can be copied/pasted to crontab. Should be able to be automagically appended to crontab with a bit more work. Tested on bash and zsh on linux,freebsd,aix

echo 'export PROMPT_COMMAND="history -a; history -c; history -r; $PROMPT_COMMAND"' >> .bashrc
while ( true ) ; do if [ $(expr $RANDOM % 2 ) -eq 0 ] ; then echo -ne "\xE2\x95\xB1" ; else echo -ne "\xE2\x95\xB2" ; fi ; done
2015-01-17 12:46:37
User: tobi
Functions: echo expr true
2

Generates labyrinth-like pattern on UTF-8 terminal in bash.

For fun ;)

mkfifo fifo; while true ; do echo "Waiting for new event"; nc -l 8080 < fifo | tee -a proxy.txt /dev/stderr | nc 192.168.0.1 80 > fifo ; done
2015-01-14 09:26:54
User: ynedelchev
Functions: echo mkfifo tee true
6

If you have a client that connects to a server via plain text protocol such as HTTP or FTP, with this command you can monitor the messages that the client sends to the server. Application level text stream will be dumped on the command line as well as saved in a file called proxy.txt.

You have to change 8080 to the local port where you want your client to connect to. Change also 192.168.0.1 to the IP address of the destination server and 80 to the port of the destination server.

Then simply point your client to localhost 8080 (or whatever you changed it to).

The traffic will be redirected to host 192.168.0.1 on port 80 (or whatever you changed them to).

Any requests from the client to the server will be dumped on the console as well as in the file "proxy.txt".

Unfortunately the responses from the server will not be dumped.

find . -type f -exec echo -n "touch -t \`echo " \; -exec echo -n {} \; -exec echo -n " | sed -E 's/.*([[:digit:]]{8})_([[:digit:]]{4})([[:digit:]]{2}).*/\1\2.\3/g'\` " \; -exec echo {} \; | sh
clear;while true;sleep 1;do for((a=1;a<=$(tput cols)/3;a++));do tput cup 0 $a;echo " " $(date);done;sleep 1;for((a;a>=1;a--));do tput cup 0 $a;echo $(date) " ";done;done
$ if check4progs cp foo mv bar rsync; then echo "needed progs avail, lets do funky stuff"; else echo "oh oh better abort now"; fi
2015-01-01 16:16:00
User: Xk2c
Functions: cp echo mv
-6

Thanks to the great grml team for this func!

You really should look at their shell configs for further usefull things!

http://git.grml.org/?p=grml-etc-core.git;a=blob_plain;f=etc/grml/script-functions;h=4d6bcea8f9beae83abd08f44155d299ea54a4a9f;hb=HEAD

# {{{ check for availability of program(s)

# usage example:

# check4progs [-s,-q,--quiet,--silent] arg [arg .... argn]

#

# with option given either of:

# -s,-q,--quiet,--silent

#

# check for available progs but produce no output

check4progs() {

[ -n "${ZSH_VERSION}" ] && emulate -L sh

local RTN=0

local oldifs="${IFS}"

local ARG d found

local VERBOSE=1

case ${1} in

-q | -s | --quiet | --silent)

VERBOSE=0

shift 1

;;

*)

;;

esac

while [ $# -gt 0 ]

do

ARG="$1"

shift

found=0

IFS=:

for d in $PATH

do

if [ -x "${d}/${ARG}" ]

then

found=1

break

fi

done

IFS="${oldifs}"

# check for availability

if [ ${found} -eq 0 ]

then

if [ ${VERBOSE} -eq 1 ]

then

printf "%s: binary not found\n" "${ARG}" >&2

fi

RTN=1

fi

done

# return non zero, if at least one prog is missing!

return $RTN

}

# }}}

echo {1..9} '* 0 #' | tr ' ' '\n' |paste - - -
echo something | awk '{ total += gsub(/yourstring/,"") } END { print total }'
2014-12-16 20:58:42
User: bugmenot
Functions: awk echo
0

Count how many times a pattern is present into a stream. It can be one or more lines. No overlapping. It means searching for aa on aaa will output 1 not 2.

for USER in /var/spool/cron/*; do echo "--- crontab for $USER ---"; cat "$USER"; done
2014-12-11 19:48:46
User: tyzbit
Functions: cat echo
0

This is not exhaustive but after checking /etc/cron* is a good way to see if there are any other jobs any users may have set.

Note: this is a repost from a comment "flatcap" made on http://www.commandlinefu.com/commands/view/3726/print-crontab-entries-for-all-the-users-that-actually-have-a-crontab#comment, for which I am grateful and I take no credit.

while sleep 1; do if [ $(echo "$(cat /proc/loadavg | cut -d' ' -f1) > .8 " | bc) -gt 0 ]; then echo -e "\n\a"$(date)" \e[5m"$(cat /proc/loadavg)"\e[0m"; ps aux --sort=-%cpu|head -n 5; fi; done
2014-12-08 15:44:40
User: tyzbit
Functions: cat echo head ps sleep
0

This checks the system load every second and if it's over a certain threshold (.8 in this example), it spits out the date, system loads and top 4 processes sorted by CPU.

Additionally, the \a in the first echo creates an audible bell.

(echo n; echo p; echo 3; echo 1; echo; echo; echo w; echo q) | /sbin/fdisk /dev/sda
netstat -nr|egrep -v "Routing|Interface|lo0"|awk '{print $5}'|sort -u| while read l; do ifconfig $l ; echo " Station Addr: `lanscan -ia|grep "$l "|cut -d ' ' -f 1`" ; done
echo $(wget http://ipecho.net/plain -q -O -)
2014-10-25 20:25:05
User: KonKar
Functions: echo wget
0

Easiest way to get the external IP address.

gcloud components list | grep "^| Not" | sed "s/|\(.*\)|\(.*\)|\(.*\)|/\2/" | xargs echo gcloud components update
2014-10-13 20:52:25
User: wires
Functions: echo grep sed xargs
0

Google Cloud SDK comes with a package manager `gcloud components` but it needs a bit of `sed` to work. Modify the "^| Not" bit to change the package selection. (The gcloud --format option is currently broken)

for i in `cat hosts_list`; do RES=`ssh myusername@${i} "ps -ef " |awk '/[p]rocessname/ {print $2}'`; test "x${RES}" = "x" && echo $i; done
2014-10-03 14:57:54
User: arlequin
Functions: awk echo test
Tags: ssh awk test ps
0

Given a hosts list, ssh one by one and echo its name only if 'processname' is not running.

echo "DISK:";df -Pl | grep -v "Filesystem" | awk '{print $5,$6}' ; echo "MEM:" ; free -mto | awk '{ print $1,$2,$3,$4 }'; echo "CPU:"; top -b -d1 -n1 | grep Cpu | awk '{print $2,$3,$4,$5,$6,$7,$8,$9}';echo "LOAD:"; cat /proc/loadavg
2014-09-29 12:43:52
User: injez
Functions: awk cat df echo free grep top
0

Monitoring system in one line :

DISK : disk space

MEM: memory ( mem , swap, Total)

CPU : all information about cpu activity

LOAD : load average

for file in $(find /var/backup -name "backup*" -type f |sort -r | tail -n +10); do rm -f $file; done ; tar czf /var/backup/backup-system-$(date "+\%Y\%m\%d\%H\%M-\%N").tgz --exclude /home/dummy /etc /home /opt 2>&- && echo "system backup ok"
2014-09-24 14:04:11
User: akiuni
Functions: date echo file find rm sort tail tar
Tags: backup Linux cron
0

this command can be added to crontab so as to execute a nightly backup of directories and store only the 10 last backup files.

for line in `docker ps | awk '{print $1}' | grep -v CONTAINER`; do docker ps | grep $line | awk '{printf $NF" "}' && echo $(( `cat /sys/fs/cgroup/memory/docker/$line*/memory.usage_in_bytes` / 1024 / 1024 ))MB ; done
echo $PATH | tr -s ':' '\n'
for I in *.CR2; do if [ `exiv2 pr -p a -u $I | grep 'xmp.Rating' | awk '{ print $4 }'` == "1" ]; then echo $I; fi; done
find . -type d -print0 | while read -d $'\0' dir; do cd "$dir"; echo " process $dir"; find . -maxdepth 1 -name "*.ogg.mp3" -exec rename 's/.ogg.mp3/.mp3/' {} \; ; cd -; done
2014-08-25 11:28:43
Functions: cd echo find read rename
2

This is probably overkill, but I have some issues when the directories have spaces in their names.

The

find . -type d -print0 | while read -d $'\0' dir; do xxx; done

loops over all the subdirectories in this place, ignoring the white spaces (to some extend).

cd "$dir"; echo " process $dir"; cd -;

goes to the directory and back. It also prints some info to check the progress.

find . -maxdepth 1 -name "*.ogg.mp3" -exec rename 's/.ogg.mp3/.mp3/' {} \;

renames the file within the current directory.

The whole should work with directories and file names that include white spaces.