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2011-03-12 - Confoo 2011 presentation
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Commands using echo

Commands using echo from sorted by
Terminal - Commands using echo - 1,115 results
echo -e "o\nn\np\n1\n\n\nw\n" | fdisk /dev/sdX
for a in $(< FILENAME); do echo "$(bc <<< $(wc -m<<<$a)-1) $a";done|sort -n
dng(){ local a;a=$(sed '/'"$1"'/!d' /etc/hosts |sed '=;'"${2-1,$}"'!d'|sed '/ /!d');echo $a|tr '\040' '\n'|nl -bp'[0-9]$'|less -E;export dn=$(echo $a|sed 's,.* ,,');export ip=$(echo $a|sed 's, .*,,');echo \$dn=$dn;echo \$ip=$ip;}
2012-04-01 23:57:09
User: argv
Functions: echo export less nl sed tr
0

usage: dng BRE [selection]

default selection is the last match

DNS is ok, but although domainnames may be easier to remember than IP numbers, it still requires typing them out. This can be error-prone. Even more so than typing IPv4 numbers, depending on the domainname, its length and complexity.

svnll(){svn log "$@"|( read; while true; do read h||break; read; m=""; while read l; do echo "$l" | grep -q '^[-]\+$'&&break; [ -z "$m" ] && m=$l; done; echo "$h % $m" | sed 's#\(.*\) | \(.*\) | \([-0-9 :]\{16\}\).* % \(.*\)#\1 \2 (\3) \4#'; done)}
2012-03-25 20:39:05
User: vhotspur
Functions: echo grep read sed
Tags: log subversion
0

Emulate (more or less) Git equivalent of

git log --format='tformat:%h %an (%cr) %s'
find . -iname '*.zip' | while read file; do unzip -l "$file" | grep -q [internal file name] && echo $file; done
2012-03-23 18:08:35
User: ricardofunke
Functions: echo file find grep read
1

This command find which of your zip (or jar) files (when you have lots of them) contains a file you're searching for. It's useful when you have a lot of zip (or jar) files and need to know in which of them the file is archived.

It's most common with .jar files when you have to know which of the .jar files contains the java class you need.

To find in jar files, you must change "zip" to "jar" in the "find" command. The [internal file name] must be changed to the file name you're searching that is archived into one of the zip/jar files.

Before run this command you must step into the directory that contains the zip or jar files.

echo text | sed $"s/./&\xCC\xB6/g"
echo text | sed "s/\(.\)/\1-/g"
2012-03-23 17:18:54
User: ppaschka
Functions: echo sed
-1

Uses Unicode combining characters to produce strikethrough effect. Since commandlinefu doesn't display Unicode properly, you will need to replace the dash in the code above with the Unicode long stroke overlay (U+0336).

alias tail='tail -n $((${LINES:-`tput lines 2>/dev/null||echo -n 80`} - 7))'
2012-03-22 02:44:11
User: AskApache
Functions: alias echo
2

Run the alias command, then issue

ps aux | tail

and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand.

${LINES:-`tput lines 2>/dev/null||echo -n 12`}

Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the default of 80.

The default for TAIL is to output the last 10 lines, this alias changes the default to output the last x lines instead, where x is the number of lines currently displayed on your terminal - 7. The -7 is there so that the top line displayed is the command you ran that used TAIL, ie the prompt.

Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux/bash-power-prompt.html )

275MB/748MB

[7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~

In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

sudo sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches
2012-03-17 08:27:58
User: StephenJudge
Functions: echo sudo sync tee
Tags: memory cache
-2

"That's it. Not much to see here. The first command writes any cache data that hasn't been written to the disk out to the disk. The second command tells the kernel to drop what's cached. Not much to it. This invalidates the write cache as well as the read cache, which is why we have the sync command first. Supposedly, it is possible to have some cached write data never make it to disk, so use it with caution, and NEVER do it on a production server. You could ... but why take the risk?

As long as you are running a post 2.6.16 kernel,..."

Source: http://ubuntuforums.org/showpost.php?p=3621283&postcount=1

lsgrp() { read GID USERS <<< "$(grep "^$1:" /etc/group | cut -d: -f3,4 | tr ':,' ' ')" ; echo -e "${USERS// /\n}" | egrep -v "^($1)?$" ; egrep :[0-9]+:$GID: /etc/passwd | cut -d: -f1 ; }
2012-03-16 09:57:33
User: livibetter
Functions: cut echo egrep read
0

I can't find the lid command on my system, there is also another complied program: http://xyne.archlinux.ca/projects/lsgrp/

for w in $(tr 'A-Z ,."()?!;:' 'a-z\n' < sample.txt); do echo ${#w} $w; done | sort -u | sort -n
2012-03-15 14:14:11
User: flatcap
Functions: echo sort tr
Tags: bash sort tr
0

Take a file and ,."()?!;: give a list of all the words in order of increasing length.

First of all use tr to map all alphabetic characters to lower case and also strip out any puntuation.

A-Z become a-z

,."()?!;: all become \n (newline)

I've ignored - (hyphen) and ' (apostrophe) because they occur in words.

Next use bash to print the length ${#w} and the word

Finally sort the list numerically (sort -n) and remove any duplicates (sort -u).

Note: sort -nu performs strangely on this list. It outputs one word per length.

seq 1 1000000 | while read i; do echo -en "\r$i"; done
for a in $(cat sample.txt); do echo "${#a} $a";done|sort -n
for a in $(cat sample.txt); do echo "$(wc -m<<<$a) $a";done|sort -n
2012-03-15 08:51:42
User: knoppix5
Functions: cat echo sort
0

optionally you can add

|cut -d' ' -f2|uniq

to the end of the command line.

echo "Click a window to start recording"; read x y W H <<< `xwininfo | grep -e Width -e Height -e Absolute | grep -oE "[[:digit:]]{1,}" | tr "\n" " "`; ffmpeg -f alsa -ac 1 -i pulse -f x11grab -s ${W}x${H} -r 25 -i :0.0+${x},${y} -sameq output.mkv
2012-03-14 19:42:28
User: joseCanciani
Functions: echo grep read tr
1

The script gets the dimensions and position of a window and calls ffmpeg to record audio and video of that window. It saves it to a file named output.mkv

while read l; do echo -e "$l"; done <1.txt >2.txt
2012-03-13 14:27:49
User: knoppix5
Functions: echo read
Tags: bash read
5

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.

step3() { s=$(echo -n $b | openssl dgst -sha1 -hmac $hmac -binary | openssl base64); signature=`for((i=0;i<${#s};i++)); do case ${s:i:1} in +) e %2B;; /) e %2F;; =) e %3D;; *) e ${s:i:1};; esac ; done` ; } ; e() { echo -n $1; }
2012-03-11 10:44:01
User: nixnax
Functions: echo
7

This is the THIRD in a set of five commands. See my other commands for the previous two.

This step creates the oauth 1.0 token as explained in http://oauth.net/core/1.0/

The token is required for a Twitter filtered stream feed (and almost all Twitter API calls)

This token is simply an encrypted version of your base string. The encryption key used is your hmac.

The last part of the command scans the Base64 token string for '+', '/', and '=' characters and converts them to percentage-hex escape codes. (URI-escapeing). This is also a good example of where the $() syntax of Bash command substitution fails, while the backtick form ` works - the right parenthesis in the case statement causes a syntax error if you try to use the $() syntax here.

See my previous two commands step1 and step2 to see how the base string variable $b and hmac variable $hmac are generated.

for i in $(seq 1 20); do while read line; do echo "$i: $line"; done<$i.py; done
watch() { while true; do echo "<Ctrl+V><Ctrl+L>Every 2.0s: $@"; date; eval "$@"; sleep 2; done }
2012-03-07 09:30:15
User: hfs
Functions: echo eval sleep watch
Tags: watch
0

Usage:

watch ls -l

Basic but usable replacement for the "watch" command for those systems which don't have it (e.g. the Solaris I'm trapped on).

Type Ctrl+V to escape the following Ctrl+L which clears the screen. It will be displayed as "^L".

for ((x=0;;x+=5)); do sleep 5; hours=$(($x/3600)); minutes=$(($x%3600/60)); seconds=$(($x%60)); echo "$hours hours $minutes minutes $seconds seconds have elapsed" | festival --tts & done
2012-03-06 22:58:43
User: mrklaw
Functions: echo sleep
0

Says time every 5 seconds in hours, minutes and seconds using festival.

for ((x=0;;x+=5)); do sleep 5; echo $x | festival --tts & done
2012-03-06 21:17:51
User: mrklaw
Functions: echo sleep
0

works the same, but uses festival instead of espeak

x=1024; y=32768; cat <(echo -e "P5\n$x $y\n255\n") <(dd if=/dev/sda1 bs=$x count=$y) > sda1.pgm
2012-03-06 03:09:16
Functions: cat dd echo
Tags: dd images pnm pgm
1

Keep width to a power of 2 to see patterns emerge. 512 is good. So is 4096 for huge maps.

PNM headers are super basic.

http://netpbm.sourceforge.net/doc/pbm.html

watch() { if [ -z "$1" ]; then echo "usage: watch interval command" return fi sec=$1 shift while test :; do clear; date=$(date); echo -e "Every "$sec"s: $@ \t\t\t\t $date"; echo $@; sleep $sec; done }
cat z.log | cut -d ':' -f1 | sort | uniq | xargs -l1 -iFF echo 'echo FF $(cat z.log | grep -e "^FF" | grep -e Timeout | wc -l )' | bash
lsof -n -P|grep FlashXX|awk '{ print "/proc/" $2 "/fd/" substr($4, 1, length($4)-1) }'|while read f;do newname=$(exiftool -FileModifyDate -FileType -t -d %Y%m%d%H%M%S $f|cut -f2|tr '\n' '.'|sed 's/\.$//');echo "$f -> $newname";cp $f ~/Vids/$newname;done
2012-02-25 01:49:45
User: mhs
Functions: awk cp cut echo grep read sed tr
8

Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.