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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!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using read from sorted by
Terminal - Commands using read - 303 results
scriptName="reorder_files.sh"; echo -e '#!/bin/sh\n' > "${scriptName}"; cat files.txt | while read file; do echo "touch ${file}; sleep 0.5;" >> "${scriptName}"; done; chmod +x "${scriptName}";
2016-04-19 11:52:00
User: programmer
Functions: cat chmod echo read

Create a bash script to change the modification time for each file in 'files.txt' such that they are in the same order as in 'files.txt'

File name for bash script specified by variable, 'scriptName'. It is made an executable once writing into it has been completed.

ls *.pdf | while read file; do newfile="${file##CS749__}"; mv "${file}" "${newfile}"; done;
ls *.pdf | while read file; do newfile="CS749__${file}"; mv "${file}" "${newfile}"; done;
touch files.txt; cat reorder_files.sh | while read line; do x=`echo $line | sed 's/touch \([a-z0-9\.]\+.*.pdf\);.*/\1/'`; echo $x >> files.txt ; done;
get_iplayer --type=radio --channel "Radio 4 Extra" | grep : | awk '{ if ( NR > 1 ) { print } }'|sed 's/:.*//' |sed '$ d' > pidlist && while read p; do get_iplayer --get --fields=pid $p; done <pidlist && rm pidlist
2016-01-16 17:20:54
User: dunryc
Functions: awk grep read rm sed

use get_iplay to download all listed content from http://www.bbc.co.uk/radio4extra run every night to make sure no episodes are missed

o=0; git log --oneline | while read l; do printf "%+9s %s\n" "HEAD~${o}" "$l"; o=$(($o+1)); done | less
[ -n "$REMOTE_USER" ] || read -p "Remote User: " -er -i "$LOGNAME" REMOTE_USER
2015-10-30 17:08:17
User: pdxdoughnut
Functions: read
Tags: read input

The read command reads input and puts it into a variable. With -i you set an initial value. In this case I used a known environment variable.

ls -1 | while read a; do mv "$a" `echo $a | sed -e 's/\ //g'`; done
bar() { foo=$(ls -rt|tail -1) && read -ep "cat $foo? <y/n> " a && [[ $a != "n" ]] && eval "cat $foo" ;}
2015-10-21 20:09:33
User: knoppix5
Functions: eval ls read tail

This command will display the file, but you can change 'cat' to anything else

(type 'n' when prompted to cancel the command or anything else to proceed).


Some hints for newbies:


unset bar

to make 'bar' function annihilated.

For permanent usage you can put this (bar) function in your .bashrc (for bash) or in .profile (for sh).


. ~/.bashrc

you can get all new inserted functions in .bashrc (so the function 'bar'

or whatever name you choose) immediately available.

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 $pid ; done
echo -n [email protected] | md5sum | (read hash dash ; echo "https://secure.gravatar.com/avatar/${hash}")