Commands using echo sorted by votes

Commands using echo (1,545)

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write the output of a command to /var/log/user.log... each line will contain $USER, making this easy to grep for.

This command is useful if you want to copy the output of a series of commands to a file, for example if you want to pastebin the output from 'uname -a', 'lspci -vvv' and 'lsmod' for video driver trouble-shooting on your favorite Linux forum. 'log' takes all the following arguments as a command to execute, with STDOUT sent to /var/log/user.log. The command is echoed to the log before it is executed. The advantages of using logger (as opposed to appending output from commands to a file) are 1) commands are always appended to the logs... you don't have to worry about clobbering your log file accidentally by using '>' rather than '>>' 2) logs are automatically cleaned up by logrotate. The following functions allow you to mark the start and end of a section of /var/log/user.log. startlog() { export LOGMARK=$(date +%Y.%m.%d_%H:%M:%S); echo "$LOGMARK.START" | logger -t $USER; } then endlog() { echo "$LOGMARK.END" | logger -t $USER; } printlog will print all lines between $LOGMARK.START and $LOGMARK.END, removing everything that is prepended to each line by logger. printlog() { sudo sed -n -e "/$LOGMARK.START/,/$LOGMARK.END/p" /var/log/user.log| sed "s/.*$USER: //"; } The following command should dump just about all the information that you could possibly want about your linux configuration into the clipboard. startlog; for cmd in 'uname -a' 'cat /etc/issue' 'dmesg' 'lsusb' 'lspci' 'sudo lshw' 'lsmod'; do log $cmd; done; endlog; printlog | xsel --clipboard This is ready for a trip to http://pastebin.com/, and you don't have to worry about leaving temporary files lying around cluttering up $HOME. Caveats: I'm sure that startlog, endlog, and printlog could use some cleanup and error checking... there are unchecked dependencies between printlog and endlog, as well as between endlog and startlog. It might be useful for 'log' to send stderr to logger as well. Show Sample Output
This is sample output - yours may be different.
```
$ log uname -a; sudo tail -2 /var/log/user.log
Sep 25 16:12:44 tiger-laptop tiger: $ uname -a
Sep 25 16:12:44 tiger-laptop tiger: Linux tiger-laptop 2.6.31-22-generic-pae #65-Ubuntu SMP Thu Sep 16 16:02:41 UTC 2010 i686 GNU/Linux
```
5

log() { (echo "\$ $@";$@) | logger -t $USER; }

bartonski · 2010-09-25 20:43:22 5
Show exit status of all portions of a piped command eg. ls |this_doesn't_exist |wc
This is sample output - yours may be different.
5

echo ${PIPESTATUS[@]}

nottings · 2010-11-01 21:46:58 3
duration of the DNS-query
This is sample output - yours may be different.
5

server=8.8.8.8; host="apple.com"; queries=128; for i in `seq $queries`; do let x+=`dig @${server} $host | grep "Query time" | cut -f 4 -d " "`; done && echo "scale=3;($x/${queries})" | bc

cas_alexi · 2010-11-25 09:52:38 4
do 'foo' until it exits successfully, pausing in between crashes

restart a buggy script when it dies. works great for "git svn fetch", which leaks memory like a sieve and eventually dies...making you restart it.
This is sample output - yours may be different.
5

until foo some args; do echo "crashed: $? respawning..." >&2; sleep 10; done

braddunbar · 2010-11-28 18:08:58 4
Email yourself after a job is done

This is a two part command that comes in really handy if you're running commands that take longer than you're willing to wait. The commands are separated by the semicolon(;) The first command is whatever you're attempting to do. The second commands emails you after the job completes. Show Sample Output
This is sample output - yours may be different.
```
mysqldump -A; echo "job done"|mail 5551231234@vzwpix.com -s'job done'
sends a txt message to your phone tell you the job is done.
```
5

<command>; echo "job done"|mail email@email.com -s'job done'

windfold · 2011-05-05 18:13:17 12
draw matrix using dot
This is sample output - yours may be different.
5

echo 'graph{node[shape=record];rankdir=LR;matrix[label="{1|2|3}|{4|5|6}|{7|8|9}",color=red]}' | dot -Tpng | display

kev · 2011-12-28 04:50:09 8
Remove all leading and trailing spaces or tabs from all lines of a text file

Bash only, no sed, no awk. Multiple spaces/tabs if exists INSIDE the line will be preserved. Empty lines stay intact, except they will be cleaned from spaces and tabs if any available.
This is sample output - yours may be different.
5

while read l; do echo -e "$l"; done <1.txt >2.txt

knoppix5 · 2012-03-13 14:27:49 6

Search for packages, ranked by popularity

This will take the packages matching a given `apt-cache search` query (a collection of AND'd words or regexps) and tell you how popular they are. This is particularly nice for those times you have to figure out which solution to use for e.g. a PDF reader or a VNC client. Substitute "ubuntu.com" for "debian.org" if you want this to use Ubuntu's data instead. Everything else will work perfectly. Show Sample Output

apt-popcon() { (echo \#rank; apt-cache search "$@" |awk '$1 !~ /^lib/ {print " "$1" "}') |grep -Ff- <(wget -qqO- http://popcon.debian.org/by_inst.gz |gunzip); }

adamhotep · 2012-09-08 00:29:31 4

Output as many input

Output of a command as input to many Show Sample Output
This is sample output - yours may be different.
```
totti@totti-lap:~/tmp$ echo 'foo' | tee >(wc -c) >(grep o) >(grep f)
foo
foo
foo
4
```
5

echo 'foo' | tee >(wc -c) >(grep o) >(grep f)

totti · 2013-01-31 09:54:18 22
Encrypt and password-protect execution of any bash script

(Please see sample output for usage) script.bash is your script, which will be crypted to script.secure script.bash --> script.secure You can execute script.secure only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Show Sample Output
This is sample output - yours may be different.
```
$ cat script.bash 

#!/bin/bash
echo "Hello, world"

$ echo "eval \"\$(dd if=\$0 bs=1 skip=XX 2>/dev/null|gpg -d 2>/dev/null)\"; exit" > script.secure; sed -i s:XX:$(stat -c%s script.secure): script.secure; gpg -c < script.bash >> script.secure; chmod +x script.secure
Enter passphrase:
Repeat passphrase:

$ ./script.secure 
Enter passphrase:

Hello, world

$ cat script.secure 
eval "$(dd if=$0 bs=1 skip=69 2>/dev/null|gpg -d 2>/dev/null)"; exit
%6&A2%&F%&B%&%4&%
```
5

echo "eval \"\$(dd if=\$0 bs=1 skip=XX 2>/dev/null|gpg -d 2>/dev/null)\"; exit" > script.secure; sed -i s:XX:$(stat -c%s script.secure): script.secure; gpg -c < script.bash >> script.secure; chmod +x script.secure

rodolfoap · 2013-03-09 11:16:48 20
Graphically show percent of mount space used

Automatically drops mount points that have non-numeric sizes (e.g. /proc). Tested in bash on Linux and AIX. Show Sample Output
This is sample output - yours may be different.
```
/                        ============= 13
/var                     ================== 18
/home                    ============================================ 44
/tmp                     == 2
/boot                    ====== 6
/dev/shm                  0
```
5

for m in `df -P | awk -F ' ' '{print $NF}' | sed -e "1d"`;do n=`df -P | grep "$m$" | awk -F ' ' '{print $5}' | cut -d% -f1`;i=0;if [[ $n =~ ^-?[0-9]+$ ]];then printf '%-25s' $m;while [ $i -lt $n ];do echo -n '=';let "i=$i+1";done;echo " $n";fi;done

drockney · 2013-07-29 20:12:39 6
Found how how much memory in kB $PID is occupying in Linux

The "proportional set size" is probably the closest representation of how much active memory a process is using in the Linux virtual memory stack. This number should also closely represent the %mem found in ps(1), htop(1), and other utilities. Show Sample Output
This is sample output - yours may be different.
```
92327
```
5

echo 0$(awk '/Pss/ {printf "+"$2}' /proc/$PID/smaps)|bc

atoponce · 2013-09-26 18:20:22 10
Prepend text to a file
This is sample output - yours may be different.
5

echo "text to prepend" | cat - file

zluyuer · 2015-07-13 02:32:12 19
Check the current price of Bitcoin in USD

Show Sample Output
This is sample output - yours may be different.
```
1 BTC = 232.7678 USD
```
5

echo "1 BTC = $(curl -s https://api.coindesk.com/v1/bpi/currentprice/usd.json | grep -o 'rate":"[^"]*' | cut -d\" -f3) USD"

cadejscroggins · 2015-09-19 00:17:02 52
Chronometer in hour format

Shorter and faster... Show Sample Output
This is sample output - yours may be different.
```
00:00:35.743165049
00:00:37.774117989
```
5

stf=$(date +%s.%N);for ((;;));do ctf=$( date +%s.%N );echo -en "\r$(date -u -d "0 $ctf sec - $stf sec" "+%H:%M:%S.%N")";done

glaudiston · 2017-01-26 14:31:33 28

Calculate days on which Friday the 13th occurs

I removed the dependency of the English language Show Sample Output

for y in $(seq 1996 2018); do echo -n "$y -> "; for m in $(seq 1 12); do NDATE=$(date --date "$y-$m-13" +%w); if [ $NDATE -eq 5 ]; then PRINTME=$(date --date "$y-$m-13" +%B);echo -n "$PRINTME "; fi; done; echo; done

ginochen · 2018-06-25 09:20:57 250

Check if your desired password is already available in haveibeenpwnd database. This command uses the API provided by HIBP
This is sample output - yours may be different.
5

function hibp() { sha1=$(echo -n "$1"|sha1sum|awk '{print toupper($0)}'|tr -d '\n'); curl -s -H $'Referer: https://haveibeenpwned.com/' https://api.pwnedpasswords.com/range/$(echo -n $sha1|cut -c1-5)|grep -i $(echo -n $sha1|cut -c6-40); }

zmonkey · 2018-08-14 07:41:55 311
Instead of saying RTFM!
This is sample output - yours may be different.
5

echo "[q]sa[ln0=aln256%Pln256/snlbx]sb729901041524823122snlbxq"|dc

wuseman1 · 2019-03-02 10:00:53 57
shell bash iterate number range with for loop

Bash's arithmetic evaluation.
This is sample output - yours may be different.
5

for((i=1;i<=10;i++)){ echo $i; }

metropolis · 2019-07-28 02:32:09 77
List all files in a folder in a git repository by last commit date

This lists all the files in a folder, then finds the commit date for them one by one, then sorts them from newest to oldest
This is sample output - yours may be different.
5

git ls-tree --name-only HEAD foldername/ | while read filename; do echo "$(git log -1 --format="%ci " -- $filename) $filename"; done | sort -r

fivestones · 2023-03-01 17:02:51 273
Check if a domain is available for purchase

A quick alias to check if a domain is already registered or if it's available for purchase. Show Sample Output
This is sample output - yours may be different.
```
$ canibuy commandlinefu.com
taken
$ canibuy commandlinekungfu.com
available
```
5

function canibuy { whois "$1" 2>/dev/null | grep -q 'Registrant' && echo "taken" || echo "available" }

tyzbit · 2023-06-21 15:01:25 181
a for loop with filling 0 format, with seq

seq allows you to format the output thanks to the -f option. This is very useful if you want to rename your files to the same format in order to be able to easily sort for example: for i in `seq 1 3 10`; do touch foo$i ;done And ls foo* | sort -n foo1 foo10 foo4 foo7 But: for i in `seq -f %02g 1 3 10`; do touch foo$i ;done So ls foo* | sort -n foo01 foo04 foo07 foo10 Show Sample Output
This is sample output - yours may be different.
```
$>for i in `seq -f %03g 5 50 111`; do echo $i ; done
005
055
105
```
4

for i in `seq -f %03g 5 50 111`; do echo $i ; done

lhb · 2009-02-17 08:41:44 6
Count down from 10

Countdown from 10 or whatever you want:) Show Sample Output
This is sample output - yours may be different.
```
10
9
8
7
6
5
4
3
2
1
```
4

for (( i = 10; i > 0; i-- )); do echo "$i"; sleep 1; done

mestr · 2009-02-18 20:31:46 7
HTTP redirect

any HTTP requests to the machine on the specified port will be redirected to http://www.whatevs.com... quick, dirty, works fine for sites w/
This is sample output - yours may be different.
4

while [ 0 ]; do echo -e "HTTP/1.1 302 Found\nLocation: http://www.whatevs.com/index.html" | nc -vvvv -l -p 80; done

wwest4 · 2009-02-19 18:04:01 9
checking space availabe on all /proc/mounts points (using Nagios check_disk)

More info here: http://nagioswiki.com/wiki/index.php/Checking_/proc/mounts_on_remote_server Show Sample Output
This is sample output - yours may be different.
```
root@nagios plugins]# pwd

/usr/lib/nagios/plugins

[root@nagios plugins]# ./check_nrpe -H monitored-server -c check_disks_proc_mounts

DISK OK - free space: / 5811 MB (59%); /boot 35 MB (57%); /opt 3401 MB (34%); /dev/shm 1948 MB (100%); /tmp 6731 MB (94%); /var 4222 MB (84%);| /=4033MB;8367;8859;0;9844 /boot=26MB;51;54;0;60 /opt=6676MB;8564;9068;0;10076 /dev/shm=0MB;1655;1753;0;1948 /tmp=395MB;6057;6413;0;7126 /var=820MB;4284;4536;0;5041
```
4

check_disk -w 15% -c 10% $(for x in $(cat /proc/mounts |awk '{print $2}')\; do echo -n " -p $x "\; done)

scubacuda · 2009-02-19 22:54:06 7
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Increment the filename of png in a given directory by one

Print the detailed statistics of transferred bytes by the firewall rules

Sort netflow packet capture

Sort netflow packet capture by unique connections excluding source port.

List only directories, one per line

Alternatively, $ ls -F | grep /\$ but will break on directories containing newlines. Or the safe, POSIX sh way (but will miss dotfiles): $ for i in *; do test -d "./$i" && printf "%s\n" "$i"; done

Print all open regular files sorted by the number of file handles open to each.

List all open files of all processes. . $ find /proc/*/fd Look through the /proc file descriptors . $ -xtype f list only symlinks to file . $ -printf "%l\n" print the symlink target . $ grep -P '^/(?!dev|proc|sys)' ignore files from /dev /proc or /sys . $ sort | uniq -c | sort -n count the results . Many processes will create and immediately delete temporary files. These can the filtered out by adding: $ ... | grep -v " (deleted)$" | ...

Optimal way of deleting huge numbers of files

This command works by rsyncing the target directory (containing the files you want to delete) with an empty directory. The '--delete' switch instructs rsync to remove files that are not present in the source directory. Since there are no files there, all the files will be deleted. I'm not clear on why it's faster than 'find -delete', but it is. Benchmarks here: https://web.archive.org/web/20130929001850/http://linuxnote.net/jianingy/en/linux/a-fast-way-to-remove-huge-number-of-files.html

list block devices

Shows all block devices in a tree with descruptions of what they are.

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)

Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Find top 10 largest files

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Commands using echo (1,545) the last day the last week the last month all time sorted by date votes

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Commands using echo (1,545)

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