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Functions

Commands using echo from sorted by
Terminal - Commands using echo - 1,336 results
echo "quit" | openssl s_client -connect facebook.com:443 | openssl x509 -noout -text | grep "DNS:" | perl -pe "s/(, )?DNS:/\n/g"
2015-08-13 22:50:45
User: lgarron
Functions: echo grep perl
Tags: openssl certificate SAN domain
1
Up
Down
Get the SAN (subjectAltName) of a site's certificate.

Based on http://stackoverflow.com/questions/13127352/checking-alternative-names-for-a-san-ssl-cert

Replace "facebook.com" with the desired hostname.

Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
Down
Randomly succeeding command

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.

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echo "text to prepend" | cat - file
2015-07-13 02:32:12
User: zluyuer
Functions: cat echo
5
Up
Down
Prepend text to a file
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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" ) ) );') $file; done
2015-07-01 00:28:06
User: westonruter
Functions: echo file touch
Tags: git
-2
Up
Down
Reset the last modified time for each file in a git repo to its last commit time
Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "display:data?" | nc "$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
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Create a PNG screenshot of Rigol Ultravision scopes attached per LAN

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

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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
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Partition a sequence of disk drives for LVM with fdisk

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.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
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Find out the active XOrg Server DISPLAY number (from outside)

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.

Show sample output | Comments (19) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: System Administration services config information
2
Up
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Listing package man page, services, config files and related rpm of a file, in one alias

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

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echo FileName | perl -nlE'sleep 1 while time-(stat)[10]<10' && echo DONE
2015-05-09 14:58:41
User: pung96
Functions: echo perl
Tags: perl while date sleep test stat
0
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Wait for file to stop changing

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

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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
Tags: while date sleep test stat
3
Up
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Wait for file to stop changing

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.

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

s/espeak/say/ on a mac

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo -e $_{1..80}'\b+'
2015-05-09 10:04:44
User: unixmonkey74668
Functions: echo
-2
Up
Down
repeat any string or char n times without spaces between
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
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Display Spinner while waiting for some process to finish

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'

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echo -e ''$_{1..80}'\b+'
2015-05-05 22:13:33
User: knoppix5
Functions: echo
3
Up
Down
repeat any string or char n times without spaces between

(here is character '+' repeated 80 times)

Sometimes needed to enhance the title of the script.

Show sample output | Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2015-05-03 01:51:27
User: knoppix5
Functions: clear date echo eval sleep tput
3
Up
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Yet Another Large Screen Clock
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
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summarize a list of IP addresses, verifying IP address and giving counts for each IP found

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.

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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
Up
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Execute a command at a given time

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

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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
Up
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Compare a remote file with a local file

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.

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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
Tags: sed fold wordwrap textwrap
1
Up
Down
Wordwrap long text string using "\n"

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"

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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
Tags: symlinks fix broken relink symlink
1
Up
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RELINK a lot of broken symlinks - FIX broken symlinks after rsync site to new server

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

find -L . -type l

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awk '{print $0+0}' <(echo -2; echo +3;)
2015-04-08 09:19:24
User: unixmonkey88472
Functions: awk echo
0
Up
Down
Removing leading + sign from numbers

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

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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 '-' ' '
2015-04-08 02:33:05
User: knoppix5
Functions: cat echo paste seq tr xargs
1
Up
Down
draw rhomb
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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
Tags: cronjob shell function crontab cron
0
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Print a cron formatted time for 2 minutes in the future (for crontab testing)

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

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echo 'export PROMPT_COMMAND="history -a; history -c; history -r; $PROMPT_COMMAND"' >> .bashrc
2015-03-09 19:57:56
User: qdrizh
Functions: echo
Tags: bashrc
1
Up
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Merge bash terminal histories
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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
Tags: bash fun pattern labyrinth
2
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Labyrinth pattern

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

For fun ;)

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