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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
count="1" ; while true ; do read next ; if [[ "$next" = "$last" ]] ; then count=$(($count+1)) ; echo "$count" ; else count="1" ; echo $count ; fi ; last="$next" ; done
2010-03-30 04:02:29
User: dabom
Functions: echo read true
Tags: bash read Game

Really bored during class so I made this...

Basically, you hold period (or whatever) and hit enter after a second and you need to make the next line of periods the same length as the previous line...

My record was 5 lines of the same length.

It's best if you do it one handed with your pointer on period and ring on enter.

ls | while read filename; do tar -czvf "$filename".tar.gz "$filename"; rm "$filename"; done
2010-03-29 08:10:38
User: Thingymebob
Functions: ls read rm tar

Compresses each file individually, creating a $fileneame.tar.gz and removes the uncompressed version, usefull if you have lots of files and don't want 1 huge archive containing them all. you could replace ls with ls *.pdf to just perform the action on pdfs for example.

rpm --querytags | egrep -v HEADERIMMUTABLE | sort | while read tag ; do rpm -q --queryformat "$tag: [%{$tag} ]\n" -p $SomeRPMfile ; done
2010-03-25 05:40:48
Functions: egrep read rpm sort

If you want to relocate a package on your own, or you just want to know what those PREIN/UN and POSTIN/UN scripts will do, this will dump out all that detail simply.

You may want to expand the egrep out other verbose flags like CHANGELOGTEXT etc, as your needs require.

It isn't clear, but the formatting around $tag is important: %{$tag} just prints out the first line, while [%{$tag }] iterates thru multi-line output, joining the lines with a space (yes, there's a space between the g and } characters. To break it out for all newlines, use [%{$tag\n}] but the output will be long.

This is aside from rpm2cpio | cpio -ivd to extract the package files.

( last ; ls -t /var/log/wtmp-2* | while read line ; do ( rm /tmp/wtmp-junk ; zcat $line 2>/dev/null || bzcat $line ) > /tmp/junk-wtmp ; last -f /tmp/junk-wtmp ; done ) | less
2010-03-16 04:17:16
Functions: last ls read rm zcat

When your wtmp files are being logrotated, here's an easy way to unpack them all on the fly to see more than a week in the past. The rm is the primitive way to prevent symlink prediction attack.

find . -iname '*.mp3' | while read song; do mpg321 ${song} -w - | oggenc -q 9 -o ${song%.mp3}.ogg -; done
2010-03-14 11:34:35
User: renich
Functions: find mpg321 read
Tags: ogg mpg321

This is not recommended... lossy -> lossy = lossier.

Still, you can do it! ;)

while read f;do echo "$f";done < <(find .)
2010-03-02 14:22:22
Functions: echo find read

Read all contents from current directory and display to stdout.

find . |while read f;do echo "$f";done
2010-03-02 14:21:15
Functions: echo find read

Read all contents from current directory and display it on stdout.

ls *.wav | while read f; do lame "$f" -o "$(echo $f | cut -d'.' -f1)".mp3; done;
uri_escape(){ echo -E "$@" | sed 's/\\/\\\\/g;s/./&\n/g' | while read -r i; do echo $i | grep -q '[a-zA-Z0-9/.:?&=]' && echo -n "$i" || printf %%%x \'"$i" done }
2010-02-13 01:39:51
User: infinull
Functions: echo grep printf read sed

This one uses hex conversion to do the converting and is in shell/sed only (should probably still use the python/perl version).

find /dev/vg00 -type b |while read L; do lvextend -m 1 $L /dev/disk/<disk> ; done
set-proxy () { P=webproxy:1234; DU="fred"; read -p "username[$DU]:" USER; printf "%b"; UN=${USER:-$DU}; read -s -p "password:" PASS; printf "%b" "\n"; export http_proxy="http://${UN}:${PASS}@$P/"; export ftp_proxy="http://${UN}:${PASS}@$P/"; }
2010-02-04 13:12:59
User: shadycraig
Functions: export printf read set

Prompts the user for username and password, that are then exported to http_proxy for use by wget, yum etc

Default user, webproxy and port are used.

Using this script prevent the cleartext user and pass being in your bash_history and on-screen

while read l; do echo $RANDOM "$l"; done | sort -n | cut -d " " -f 2-
2010-02-03 22:36:34
User: ketil
Functions: cut echo read sort

If you need to randomize the lines in a file, but have an old sort commands that doesn't support the -R option, this could be helpful. It's easy enough to remember so that you can create it as a script and use that.

It ain't real fast. It ain't safe. It ain't super random. Do not use it on untrusted data. It requires bash for the $RANDOM variable to work.

find . -maxdepth 1 -type f| xargs sha1sum | sed 's/^\(\w*\)\s*\(.*\)/\2 \1/' | while read LINE; do mv $LINE; done
(IFS=; sed 's/^[]0;[^^G]*^G/^M/g' <SessionLog> | while read -n 1 ITEM; do [ "$ITEM" = "^M" ] && ITEM=$'\n'; echo -ne "$ITEM"; sleep 0.05; done; echo)
2010-01-20 16:11:32
User: jgc
Functions: echo read sed sleep
Tags: read script

This command will play back each keystroke in a session log recorded using the script command. You'll need to replace the ^[ ^G and ^M characters with CTRL-[, CTRL-G and CTRL-M. To do this you need to press CTRL-V CTRL-[ or CTRL-V CTRL-G or CTRL-V CTRL-M.

You can adjust the playback typing speed by modifying the sleep.

If you're not bothered about seeing each keypress then you could just use:

cat session.log
removedir(){ read -p "Delete the current directory $PWD ? " human;if [ "$human" = "yes" ]; then [ -z "${PWD##*/}" ] && { echo "$PWD not set" >&2;return 1;}; rm -Rf ../"${PWD##*/}"/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }
removedir () { echo "Deleting the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }
2010-01-17 11:34:38
User: oshazard
Functions: basename cd echo read rm sed


Version 1.1

removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=$(echo "$PWD" | sed 's/ /\\ /g'); foo=$(basename "$blah"); rm -Rf ../$foo/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }


Folders with spaces

Version 1.0

removedir () { echo "You are about to delete the current directory $PWD Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }


Hidden directories (.dotdirectory)

Version 0.9

rmdir () { echo "You are about to delete the current directory $PWD. Are you sure?"; read human; if [[ "$human" = "yes" ]]; then blah=`basename $PWD`; rm -Rf ../$blah/ && cd ..; else echo "I'm watching you" | pv -qL 10; fi; }

Removes current directory with recursive and force flags plus basic human check. When prompted type yes

1. [user@host ~]$ ls

foo bar

2. [user@host ~]$ cd foo

3. [user@host foo]$ removedir

4. yes

5. rm -Rf foo/

6. [user@host ~]$

7. [user@host ~]$ ls


ps -ef | grep user | awk '{print $2}' | while read pid; do echo $pid ; pfiles $pid| grep portnum; done
2010-01-11 12:34:51
User: sharfah
Functions: awk echo grep ps read

My old Solaris server does not have lsof, so I have to use pfiles.

echo 'Desktop SPAM!!!' | while read SPAM_OUT; do notify-send "$SPAM_OUT"; done
2009-12-31 15:38:35
User: michelsberg
Functions: echo read
Tags: notify-send

Route output to notify-send to show nice messages on the desktop, e.g. title and interpreter of the current radio stream

read enterKey
2009-12-29 00:18:32
User: bbmarek
Functions: read
Tags: bash read

how to finish command or script without any output

getent shadow | while IFS=: read a b c; do grep -q '!' <<< "$b" && echo "$a LOCKED" || echo "$a not locked"; done
2009-12-18 15:24:19
User: sputnick
Functions: echo getent grep read
man 5 shadow

I think it's more reliable, because

passwd -S

dont show "locked" but "L" as second field on my Archlinux for a particular user.

( unixhome alternative ).

awk -F":" '{ print $1 }' /etc/passwd | while read UU ; do STATUS=$(passwd -S ${UU} | grep locked 2>/dev/null) ; if [[ ! -z ${STATUS} ]] ; then echo "Account ${UU} is locked." ; fi ; done
A=1;B=100;X=0;C=0;N=$[$RANDOM%$B+1];until [ $X -eq $N ];do read -p "N between $A and $B. Guess? " X;C=$(($C+1));A=$(($X<$N?$X:$A));B=$(($X>$N?$X:$B));done;echo "Took you $C tries, Einstein";
2009-12-16 13:24:23
User: rodolfoap
Functions: read
Tags: Game

Felt like I need to win the lottery, and wrote this command so I train and develop my guessing abilities.

while [ 1 ]; do banner 'ze missiles, zey are coming! ' | while IFS="\n" read l; do echo "$l"; sleep 0.01; done; done
2009-12-14 07:40:07
User: craigds
Functions: banner echo read sleep

Displays a scrolling banner which loops until you hit Ctrl-C to terminate it.

Make sure you finish your banner message with a space so it will loop nicely.

while read str; do echo "$((++i)) - $str"; done < infile
2009-12-09 15:11:25
User: putnamhill
Functions: echo read
Tags: bash

Hi glaudiston, you can save a few chars by leaving out cat and pipe and still enjoy the added flexibility.

cat infile | while read str; do echo "$((++i)) - $str" ; done;
2009-12-09 14:05:09
User: glaudiston
Functions: cat echo read

Yep, is hard, but is a way more flexible using pipe.