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Commands using printf from sorted by
Terminal - Commands using printf - 149 results
for i in {1..6}; do printf "%0.2X:" $[ $RANDOM % 0x100 ]; done | sed 's/:$/\n/'
2010-12-07 19:26:58
User: forcefsck
Functions: printf sed
Tags: Network bash mac
2

Shorter and more straightforward.

Also in perl:

perl -e 'print join(":", map { sprintf "%0.2X",rand(256) }(1..6))."\n"'
alias duh='dulist=$(du -sh */); for i in T G M K; do printf "$dulist"|egrep "^[0-9\.]+$i" | sort -rn; done'
2010-12-07 11:11:26
User: forcefsck
Functions: alias du egrep printf sort
Tags: disk usage
-1

Alias to produce a list of all subdir sizes in current dir, in reverse order and human readable units. du is executed only once. Remove the slash after the asterisk to include files.

printf "$string" | md5sum
tail -f file |xargs -IX printf "$(date -u)\t%s\n" X
echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=' ') f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"
2010-11-24 23:49:21
User: unefunge
Functions: echo printf tr xargs
4

displays current time in "binary clock" format

(loosely) inspired by: http://www.thinkgeek.com/homeoffice/lights/59e0/

"Decoding":

8421

.... - 1st hour digit: 0

*..* - 2nd hour digit: 9 (8+1)

.*.. - 1st minutes digit: 4

*..* - 2nd minutes digit: 9 (8+1)

Prompt-command version:

PROMPT_COMMAND='echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=" ") f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"'

PROMPT_COMMAND='seq $COLUMNS | xargs -IX printf "%Xs\r" @'
tail -f file | while read line; do printf "$(date -u '+%F %T%z')\t$line\n"; done
2010-11-24 05:50:12
User: derekschrock
Functions: file printf read tail
Tags: tail date
3

Should be a bit more portable since echo -e/n and date's -Ins are not.

for file in $( vmrun list | grep 'vmx$' | sort ); do printf "% 40s %s M\n" $(echo "$( echo -n ${file}:\ ; grep memsize $file )" | sed -e 's/.*\///' -e 's/"//g' -e 's/memsize.=//'); done;
2010-11-19 06:14:11
Functions: echo file grep printf sed sort
Tags: vmware
-1

So your boss wants to know how much memory has been assigned to each virtual machine running on your server... here's how to nab that information from the command line while logged in to that server

for i in ???.jpg; do mv $i $(printf %04d $(basename $i .jpg) ).jpg ; done
2010-11-18 23:48:41
User: carlesso
Functions: basename mv printf
Tags: rename cp printf
5

Useful if you have a list of images called 1 2 3 4 and so on, you can adapt it to rewrite it as 4 (in this example) 0-padded number.

OFFS=30;LZ=6;FF=$(printf %%0%dd $LZ);for F in *.jpg;do NF="${F%.jpg}";NF="${NF/#+(0)/}";NF=$[NF+OFFS];NF="$(printf $FF $NF)".jpg;if [ "$F" != "$NF" ];then mv -iv "$F" "$NF";fi;done
2010-11-08 22:48:56
Functions: mv printf
2

When you have different digital cameras, different people, friends and you want to merge all those pictures together, then you get files with same names or files with 3 and 4 digit numbers etc. The result is a mess if you copy it together into one directory.

But if you can add an offset to the picture number and set the number of leading zeros in the file name's number then you can manage.

OFFS != 0 and LZ the same as the files currently have is not supported. Or left as an exercise, hoho ;)

I love NF="${NF/#+(0)/}",it looks like a magic bash spell.

mplayer -vo null -ao null -frames 0 -identify movie.avi | awk '{FS="="}; /ID_LENGTH/{ H=int($2/3600); M=int(($2-H*3600)/60); S=int($2%60); printf "%d:%02d:%02d\n",H,M,S}'
2010-10-13 14:51:41
User: PNuts
Functions: awk printf
0

Prints movie length in H:MM:SS format with appropriate leading zeros.

rd(){ while read a ;do printf "$a\n";sleep ${1-1};done ;} # usage: rd < file ; or ... | rd
2010-10-03 04:16:03
User: argv
Functions: file printf read sleep
2

usage examples

ls largedir |rd

lynx -dump largewebsite.com |rd

rd < largelogfile

jb() { if [ -z $1 ];then printf 'usage:\njb <"date and/or time"> <"commandline"> &\nsee parsedate(3) strftime(3)\n';else t1=$(date +%s); t2=$(date -d "$1" +%s) ;sleep $(expr $t2 - $t1);$2 ;fi ;}
2010-08-26 23:50:42
User: argv
Functions: date expr printf
2

EXAMPLES

jb "next sun 12pm" "/bin/sh ~you/1.sh" &

jb "2010-08-29 12:00:00" "~you/1.sh" &

jb "29aug2010 gmt" ". ~you/1.sh" &

jb 12:00p.m. "nohup ./1.sh" &

jb 1min "echo stop!" &

SEE ALSO

parsedate(3) strftime(3)

cls(){ printf "\033c";} or, if no printf, cat > c ;<ctrl+v> <ctrl+[>c <enter><ctrl-d> c(){ cat c;} #usage: c
printf $(( echo "obase=16;$(echo $$$(date +%s%N))"|bc; ip link show|sed -n '/eth/ {N; p}'|grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'|head -c 17 )|tr -d [:space:][:punct:] |sed 's/[[:xdigit:]]\{2\}/\\x&/g')|sha1sum|head -c 32; echo
2010-07-14 14:04:53
User: camocrazed
Functions: echo grep head link printf sed tr
Tags: uuid
0

first off, if you just want a random UUID, here's the actual command to use:

uuidgen

Your chances of finding a duplicate after running this nonstop for a year are about the same as being hit by a meteorite before finishing this sentence

The reason for the command I have is that it's more provably unique than the one that uuidgen creates. uuidgen creates a random one by default, or an unencrypted one based on time and network address if you give it the -t option.

Mine uses the mac address of the ethernet interface, the process id of the caller, and the system time down to nanosecond resolution, which is provably unique over all computers past, present, and future, subject to collisions in the cryptographic hash used, and the uniqueness of your mac address.

Warning: feel free to experiment, but be warned that the stdin of the hash is binary data at that point, which may mess up your terminal if you don't pipe it into something. If it does mess up though, just type

reset
echo "${1}" | egrep '^[[:digit:]]*$' ; if [ "$?" -eq 0 ] ; then sed -i "${1}"d $HOME/.ssh/known_hosts ; else printf "\tYou must enter a number!\n\n" ; exit 1 ; fi
2010-07-11 23:09:11
User: DaveQB
Functions: echo egrep exit printf sed
Tags: sed
-13

I have this as a file called deletekey in my ~/bin.

Makes life a little easier.

grep '^MemFree:' /proc/meminfo | awk '{ mem=($2)/(1024) ; printf "%0.0f MB\n", mem }'
2010-06-30 18:33:29
User: dbbolton
Functions: awk grep printf
4

This will show the amount of physical RAM that is left unused by the system.

L(){ l=`builtin printf %${2:-$COLUMNS}s` && echo -e "${l// /${1:-=}}"; }
2

One of the first functions programmers learn is how to print a line. This is my 100% bash builtin function to do it, which makes it as optimal as a function can be. The COLUMNS environment variable is also set by bash (including bash resetting its value when you resize your term) so its very efficient. I like pretty-output in my shells and have experimented with several ways to output a line the width of the screen using a minimal amount of code. This is like version 9,000 lol.

This function is what I use, though when using colors or other terminal features I create separate functions that call this one, since this is the lowest level type of function. It might be better named printl(), but since I use it so much it's more optimal to have the name contain less chars (both for my programming and for the internal workings).

If you do use terminal escapes this will reset to default.

tput sgr0

For implementation ideas, check my

http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

echo -n "convert " > itcombino.sh; printf "IMG_%00004u.png " {1..1121} >> itcombino.sh; echo -n "-layers merge _final.png" >> itcombino.sh; chmod +x itcombino.sh && ./itcombino.sh
2010-05-22 03:56:30
User: IsraelTorres
Functions: chmod echo printf
1

This one liner; combines all sequentially numbered files; in this example IMG_0001.png to IMG_1121.png by generating the shell script, making the shell script executable and then running the shell script to combine the 1121 png into a single png file named _final.png

tested on Mac OS X 10.6.3 with ImageMagick 6.5.8-0 2009-11-22 Q16 http://www.imagemagick.org

sortwc () { local L;while read -r L;do builtin printf "${#L}@%s\n" "$L";done|sort -n|sed -u 's/^[^@]*@//'; }
2010-05-20 20:13:52
User: AskApache
Functions: printf read sed sort
2

This provides a way to sort output based on the length of the line, so that shorter lines appear before longer lines. It's an addon to the sort that I've wanted for years, sometimes it's very useful. Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

s='s=\47%s\47; printf "$s" "$s"'; printf "$s" "$s"
2010-05-09 16:52:58
User: fpunktk
Functions: printf
4

this command prints itself out. it doesn't need to be stored in a file and it isn't as easy as

echo $BASH_COMMAND

for information on quines see http://en.wikipedia.org/wiki/Quine_(computing)

cd /some/empty/folder/website_diffs/sitename && wget -N http://domain.com/ 2>&1 |grep -q "o newer" || printf "Sites web page appears to have updated.\n\nSuggest you check it out.\n\n"|mail -s "Sites page updated." david@email.com
2010-05-09 07:28:42
User: DaveQB
Functions: cd grep mail printf wget
2

A cronjob command line to email someone when a webpages homepage is updated.

pmap $(pgrep [ProcessName] -n) | gawk '/total/ { a=strtonum($2); b=int(a/1024); printf b};'
printf "\n%25s%10sTOTAL\n" 'FILE TYPE' ' '; for ext in $(find . -iname \*.* | egrep -o '\.[^[:space:].]+$' | egrep -v '\.svn*' | sort -f | uniq -i); do count=$(find . -iname \*$ext | wc -l); printf "%25s%10s%d\n" $ext ' ' $count; done
2010-04-16 21:12:11
User: rkulla
Functions: egrep find printf sort uniq wc
0

I created this command to give me a quick overview of how many file types a directory, and all its subdirectories, contains. It works based off file extension, rather than file(1)'s magic output, because it ended up being more accurate and less confusing.

Files that don't have an ext (README) are generally not important for me to want to count, but you're free to customize this fit your needs.

printf -v row "%${COLUMNS}s"; echo ${row// /#}
2010-04-13 21:56:46
User: dennisw
Functions: echo printf
Tags: tr tput printf
4

Pure Bash

This will print a row of characters the width of the screen without using any external executables. In some cases, COLUMNS may not be set. Here is an alternative that uses tput to generate a default if that's the case. And it still avoids using tr.

printf -v row "%${COLUMNS:-$(tput cols)}s"; echo ${row// /#}

The only disadvantage to either one is that they create a variable.