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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands using read from sorted by
Terminal - Commands using read - 295 results
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

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.

git rev-list --reverse --topo-order master... | while read rev; do git checkout preview; git cherry-pick $rev || break; done
2015-04-23 14:28:06
User: shadyvb
Functions: read
Tags: git preview

Creating feature-branches off master, and trying to merge them in an integration branch (preview), sometimes causes conflicts because the feature-branch might hold changes from 'master' that aren't on preview yet. So this ensures only the commits added to the feature-branch are moved to integration (preview).

Note: This assumes you're currently on the feature-branch. Adjust 'master/preview' branch names to suit your environment.

find -name pom.xml | while read f; do cd $(dirname "$f"); mvn clean; cd -; done;
2015-04-15 21:24:49
User: glaudiston
Functions: cd dirname find read

this command is used to locate all pom.xml files, access the dir and do a mvn clean, but I do recommend you to disable network interfaces to not download dependencies packages to be faster.

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

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

find -L . -type l

ls | while read line; do ln -s "$(pwd)/$line" "/usr/bin/$line"; done
find . -type f -name "*\?*" | while read f;do mv "$f" "${f//[^0-9A-Za-z.\/\(\)\ ]/_}";done
2014-11-28 14:55:27
User: miccaman
Functions: find mv read
Tags: bash find mv

replace all "?" characters in filename to underscore

find . -type d -name "*\?*" | while read f;do mv "$f" "${f//[^0-9A-Za-z.\/\(\)\ ]/_}";done
2014-11-28 14:52:46
User: miccaman
Functions: find mv read
Tags: bash find mv

rename all dirs with "?" char in name, leave spaces and () in place

find ./i18n -name "*.po" | while read f; do msgfmt $f -o ${f%.po}.mo; done
2014-11-14 19:14:35
User: sergeylukin
Functions: find read

This command takes all `.po` files inside `i18n` directory and compiles them to `.mo` files with same basename

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
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

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


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.

hl() { while read -r; do printf '%s\n' "$(perl -p -e 's/('"$1"')/\a\e[7m$1\e[0m/g' <<< "$REPLY")"; done; }
cat h.txt| while read line; do curl -s -X POST 'https://www.virustotal.com/vtapi/v2/file/report' --form apikey="APIKEY" --form resource="$line"|awk -F'positives\":' '{print "VTHits"$2}'|awk -F' ' '{print $1" "$2$5$6}'|sed 's/["}]//g' && sleep 15; done
find . -type f -iname '*.flac' | while read i; do mv -- "$i" "$i.tmp"; gst-launch filesrc location="$i.tmp" ! flacdec ! flacenc quality=8 ! filesink location="${i%.tmp}"; rm -- "$i.tmp"; done
2014-07-10 19:21:22
User: qdrizh
Functions: find mv read rm

Sometimes I get FLAC files that RhythmBox can't play but VLC can. So I re-encode them using GStreamer at highest compression.

git verify-pack -v .git/objects/pack/pack-*.idx | grep blob | sort -k3nr | head | while read s x b x; do git rev-list --all --objects | grep $s | awk '{print "'"$b"'",$0;}'; done
pgrep 'sleep' | while read pid; do pstree -sa -H$pid $pid ; done
echo -n test@example.com | md5sum | (read hash dash ; echo "https://secure.gravatar.com/avatar/${hash}")
cat dictionary.txt|while read a; do echo $a|cryptsetup luksOpen /dev/sda5 sda5 $a && echo KEY FOUND: $a; done
2014-04-16 18:49:53
User: rodolfoap
Functions: cat echo read

Lost your luks passphrase? You can always bruteforce from the command line. See the sample output, a simple command using a dictionary.

find . -name '*.mp3' | sort | while read -r mp3; do echo -e "<h3>$mp3</h3>\n<audio controls src=\"$mp3\"></audio>"; done > index.html; python -m http.server
2014-03-24 15:01:49
User: hendry
Functions: echo find python read sort
Tags: audio browser

I tried a few curses based mp3 players for playing back choir practice songs for my wife.

Unfortunately none of the ones I tried were capable of scrubbing a track.

Firefox saves the day.

while read i; do [ ${#i} -gt 72 ] && echo "$i"; done < /path/to/file
2014-03-20 12:27:06
User: flatcap
Functions: echo read

Filter out lines of input that contain 72, or fewer, characters.

This uses bash only. ${#i} is the number of characters in variable i.

alias ...='while read line; do echo -n "."; done && echo ""'
read -p "Please enter the 4chan url: "|egrep '//i.4cdn.org/[a-z0-9]+/src/([0-9]*).(jpg|png|gif)' - -o|nl -s https:|cut -c7-|uniq|wget -nc -i - --random-wait
inotifywait -mr -e CREATE $HOME/bin/ | while read i; do chmod +x $(echo "$i" | sed 's/ \S* //'); done
find . -type d| while read i; do echo $(ls -1 "$i"|wc -m) $(du -s "$i"); done|sort -s -n -k1,1 -k2,2 |awk -F'[ \t]+' '{ idx=$1$2; if (array[idx] == 1) {print} else if (array[idx]) {print array[idx]; print; array[idx]=1} else {array[idx]=$0}}'
2014-02-25 22:50:09
User: knoppix5
Functions: awk du echo find ls read sort wc

Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical.

if in doubt apply:

diff -rq path_to_dir1 path_to_dir2

AWK function taken from here:


(read -r passphrase; b58encode 80$( brainwallet_exponent "$passphrase" )$( brainwallet_checksum "$passphrase" ))

A bitcoin "brainwallet" is a secret passphrase you carry in the "wallet" of your brain.

The Bitcoin Brainwallet Private Key Calculator calculates the standard base58 encoded bitcoin private key from your "brainwallet" passphrase.

The private key is the most important bitcoin number. All other numbers can be derived from it.

This command uses 3 other functions - all 3 are defined on my user page:

1) brainwallet_exponent() - search for Bitcoin Brainwallet Exponent Calculator

2) brainwallet_checksum() - search for Bitcoin Brainwallet Exponent Calculator

3) b58encode() - search for Bitcoin Brainwallet Base58 Encoder

Do make sure you use really strong, unpredictable passphrases (30+ characters)!

http:brainwallet.org can be used to check the accuracy of this calculator.

function b58encode () { local b58_lookup_table=({1..9} {A..H} {J..N} {P..Z} {a..k} {m..z}); bc<<<"obase=58;ibase=16;${1^^}"|(read -a s; for b58_index in "${s[@]}" ; do printf %s ${b58_lookup_table[ 10#"$b58_index" ]}; done); }

A bitcoin "brainwallet" is a secret passphrase you carry in your brain.

The Bitcoin Brainwallet Private Key Base58 Encoder is the third of three functions needed to calculate a bitcoin PRIVATE key from your "brainwallet" passphrase.

This base58 encoder uses the obase parameter of the amazing bc utility to convert from ASCII-hex to base58. Tech note: bc inserts line continuation backslashes, but the "read s" command automatically strips them out.

I hope that one day base58 will, like base64, be added to the amazing openssl utility.