Commands using echo sorted by votes

Commands using echo (1,545)

sorted by

seq can produce the same thing as Perl's ... operator.

Optionally, one can use {1..50} instead of seq. E.g. for i in {1..50} ; do echo Iteration $i ; done Show Sample Output
This is sample output - yours may be different.
```
Iteration 1
Iteration 2
Iteration 3
Iteration 4
Iteration 5
etc..
```
8

for i in $(seq 1 50) ; do echo Iteration $i ; done

abcde · 2009-02-08 23:03:31 13
Export MySQL query as .csv file

This command converts a MySQL query directly into a .csv (Comma Seperated Value)-file. Show Sample Output
This is sample output - yours may be different.
```
no output
```
8

echo "SELECT * FROM table; " | mysql -u root -p${MYSQLROOTPW} databasename | sed 's/\t/","/g;s/^/"/;s/$/"/;s/\n//g' > outfile.csv

jacquesloonen · 2009-02-16 18:55:18 10
Set an alarm to wake up [2]

Set an alarm to starts in specific time. Show Sample Output
This is sample output - yours may be different.
```
For instance:
echo "aplay /media/dados/audio/geral/Yahoo.wav" | at 16:28
```
8

echo "aplay path/to/song" |at [time]

brausen · 2009-06-25 19:33:37 12
IFS - use entire lines in your for cycles

When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to . Show Sample Output
This is sample output - yours may be different.
```
$ cat file
line one
line two
$ for i in `cat file`; do echo $i; done
line
one
line
two
$ export IFS=$(echo -e "\n")
$ for i in `cat file`; do echo $i; done
line one
line two
```
8

export IFS=$(echo -e "\n")

darkpand · 2009-07-09 15:25:37 9
Check availability of Websites based on HTTP_CODE
This is sample output - yours may be different.
8

urls=('www.ubuntu.com' 'google.com'); for i in ${urls[@]}; do http_code=$(curl -I -s $i -w %{http_code}); echo $i status: ${http_code:9:3}; done

Code_Bleu · 2009-08-17 16:24:26 5
is today the end of the month?
This is sample output - yours may be different.
8

[ `date --date='next day' +'%B'` == `date +'%B'` ] || echo 'end of month'

pc1500 · 2009-09-29 11:46:35 21
A little bash daemon =)

A little bash daemon
This is sample output - yours may be different.
8

echo "Starting Daemon"; ( while :; do sleep 15; echo "I am still running =]"; done ) & disown -h -ar $!

tatsu · 2009-09-30 16:00:13 33
Using tput to save, clear and restore the terminal contents

Very useful for interactive scripts where you would like to return the terminal contents to its original state before the script was run. This would be similar to how vi exits and returns you to your original terminal screen. Save and clear the terminal contents with: tput smcup Execute some commands, then restore the saved terminal contents with: tput rmcup
This is sample output - yours may be different.
8

tput smcup; echo "Doing some things..."; sleep 2; tput rmcup

jgc · 2009-10-08 16:48:04 24
Check a server is up. If it isn't mail me.

Joker wants an email if the Brand X server is down. Set a cron job for every 5 mins with this line and he gets an email when/if a ping takes longer than 3 seconds. Show Sample Output
This is sample output - yours may be different.
```
An email saying "brandx.jp.sme ping failed"
```
8

ping -q -c1 -w3 brandx.jp.sme 2&>1 /dev/null || echo brandx.jp.sme ping failed | mail -ne -s'Server unavailable' joker@jp.co.uk

mccalni · 2009-10-13 14:13:04 16
show ls colors with demo

This can show all ls colors, with a demo.
This is sample output - yours may be different.
8

echo $LS_COLORS | sed 's/:/\n/g' | awk -F= '!/^$/{printf("%s \x1b[%smdemo\x1b[0m\n",$0,$2)}'

bones7456 · 2009-12-15 01:17:46 7
easily find megabyte eating files or directories

Show Sample Output
This is sample output - yours may be different.
```
ruin:~$ ducks
229G	total
156G	Music
25G	Pictures
18G	Downloads
16G	Movies
1G	Documents
286M	code
172k	.ssh
112k	bin
48k	.git_bash_completion
```
8

du -cks * | sort -rn | while read size fname; do for unit in k M G T P E Z Y; do if [ $size -lt 1024 ]; then echo -e "${size}${unit}\t${fname}"; break; fi; size=$((size/1024)); done; done

askedrelic · 2010-04-05 17:09:14 5
Replace multiple file extensions with a single extension

The above is just a prove of concept based around the nested bash substitution. This could be useful in situations where you're in a directory with many filetypes but you only want to convert a few. for f in *.bmp *.jpg *.tga; do convert $f ${f%.*}.png; done or you can use ls | egrep to get more specific... but be warned, files with spaces will cause a ruckus with expansion but the bash for loop uses a space delimited list. for f in $(ls | egrep "bmp$|jpg$|tga$"); do convert $f ${f%.*}.png; done I'm guessing some people will still prefer doing it the sed way but I thought the concept of this one was pretty neat. It will help me remember bash substitutions a little better :-P Show Sample Output
This is sample output - yours may be different.
```
t1.png
t2.png
t3.png
```
8

for f in t1.bmp t2.jpg t3.tga; do echo ${f%.*}.png; done

zed · 2010-07-09 00:38:53 3
Perl One Liner to Generate a Random IP Address

A bash version.
This is sample output - yours may be different.
8

echo $((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256)).$((RANDOM%256))

putnamhill · 2011-01-16 23:02:01 7
Create cheap and easy index.html file

If your admin has disabled Apache's directory index feature but you want to have a cheap way to enable it for one folder, this command will just create an index.html file with a link to each file in the directory (including the index.html file, which is not ideal but makes the command much simpler). The HTML isn't even remotely compliant, but it could easily be improved on. Also, the command needs to be run each time a file is added or removed to update the index.html file. Show Sample Output
This is sample output - yours may be different.
```
 <li><a href='index.html'>index.html</a>
 <li><a href='Unallocated Space-loft1.png'>Unallocated Space-loft1.png</a>
 <li><a href='Unallocated Space-loft2.png'>Unallocated Space-loft2.png</a>
 <li><a href='Unallocated Space-loft3.png'>Unallocated Space-loft3.png</a>
 <li><a href='Unallocated Space-loft4.png'>Unallocated Space-loft4.png</a>
 <li><a href='Unallocated Space.sh3d'>Unallocated Space.sh3d</a>
```
8

for i in *; do echo "<li><a href='$i'>$i</a>"; done > index.html

TexasDex · 2011-05-02 21:31:00 5
Enter parameter if empty (script becomes interactive when parameters are missing)

Can be used for command line parameters too. If you have a more complicated way of entering values (validation, GUI, ...), then write a function i.e. EnterValue() that echoes the value and then you can write: param=${param:-$(EnterValue)}
This is sample output - yours may be different.
8

param=${param:-$(read -p "Enter parameter: "; echo "$REPLY")}

frans · 2011-09-08 20:48:31 4
Capitalize first letter of each word in a string

I find it useless but definitely simpler than #9230 Show Sample Output
This is sample output - yours may be different.
```
read -ra words <<< "one two three" && echo "${words[@]^}"
One Two Three
```
8

read -ra words <<< "<sentence>" && echo "${words[@]^}"

RanyAlbeg · 2011-09-10 02:46:42 7
Clear filesystem memory cache

Found here: http://ubuntuforums.org/showthread.php?t=589975
This is sample output - yours may be different.
8

sync && echo 3 | sudo tee /proc/sys/vm/drop_caches

mariusbutuc · 2011-10-18 15:22:25 19
Keep a copy of the raw Youtube FLV,MP4,etc stored in /tmp/

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.
This is sample output - yours may be different.
8

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

mhs · 2012-02-25 01:49:45 5
Create A Continuous Yahoo! News Ticker For The Terminal

This creates a permanent stock ticker in the terminal. it has scrolling action and refreshes when each cycle is done to get the latest news.
This is sample output - yours may be different.
8

while true;do n="$(curl -s http://news.yahoo.com/rss/|sed 's/</\n/g'|grep "title>"|sed -e '/^\// d' -e 's/title>/---------- /g' -e '1,3d'|tr '\n' ' ')";for i in $(eval echo {0..${#n}});do echo -ne "\e[s\e[0;0H${n:$i:$COLUMNS}\e[u";sleep .15;done;done &

SQUIIDUX · 2012-11-17 23:56:17 14
create a nicely formatted example of a shell command and its output

Shell function which takes a bash command as its input, and displays the following formatted output: EXAMPLE: command OUTPUT: output from command Show Sample Output
This is sample output - yours may be different.
```
EXAMPLE:

    example ls -l

OUTPUT:

    EXAMPLE:
    
        ls -l
    
    OUTPUT:
    
        total 0
        -rw-rw-r-- 1 bartonc bartonc 0 Nov 10 13:58 a
        -rw-rw-r-- 1 bartonc bartonc 0 Nov 10 13:58 b
        -rw-rw-r-- 1 bartonc bartonc 0 Nov 10 13:58 c
```
8

example() { echo "EXAMPLE:"; echo; echo " $@"; echo; echo "OUTPUT:"; echo ; eval "$@" | sed 's/^/ /'; }

bartonski · 2019-11-10 19:08:23 127
Quick way to sum every numbers in a file written line by line

If you have a file full of numbers written line by line, you can sum every line to get the total. With a file like this: 3443535 9878977 67554 987798 232324 you will got: 14610188
This is sample output - yours may be different.
7

(sed 's/^/x+=/' [yourfile] ; echo x) | bc

michelem · 2009-02-06 08:25:43 14
know the current running shell (the true)

Return the current shell. It is better than print $SHELL which can sometimes return a false value. Show Sample Output
This is sample output - yours may be different.
```
/usr/bin/zsh
```
7

echo $0

yogsototh · 2009-02-11 08:58:01 12
Force machine to reboot no matter what (even if /sbin/shutdown is hanging)

This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.
This is sample output - yours may be different.
7

echo 1 > /proc/sys/kernel/sysrq; echo b > /proc/sysrq-trigger

tsaavik · 2009-02-20 00:37:18 8
Synthesize text as speech

The Festival Speech Synthesis System converts text into sound. Or: links -dump http://youfavoritewebsite.com | festival --tts Show Sample Output
This is sample output - yours may be different.
```
Put up your speaker volume to hear the message.
```
7

echo "hello world" | festival --tts

jacquesloonen · 2009-02-20 14:00:50 12
split a string (2)
This is sample output - yours may be different.
7

read VAR1 VAR2 VAR3 < <(echo aa bb cc); echo $VAR2

mikeda · 2009-02-22 10:05:50 9
‹ First < 3 4 5 6 7 > Last ›

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands

Check These Out

Know which modules are loaded on an Apache server

This let you know which modules has loaded the Apache server, very useful to know if the mod_rewrite is ready to use.

Watch the size of a directory using figlet

You can substitute /home/$USER with any path you like.

Insert a line at the top of a text file without sed or awk or bash loops

Just use '-' to use STDIN as an additional input to 'cat'

Encode a file to MPEG4 format

Encode video.avi into newvideo.avi using the libav codec to produce an MPEG4 file with a bitrate of 800

Donwload media from *.rm from an url of type htttp://.../*.ram

Exclude inserting a table from a sql import

Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

Google URL shortener

(1) required: python-googl ( install by: pip install python-googl ) (2) get from google API console https://code.google.com/apis/console/

Google voice recognition "API"

The FLAC audio must be encoded at 16000Hz sampling rate (SoX is your friend). Outputs a short JSON string, the actual speech is in the hypotheses->utterance, the accuracy is stored in hypotheses->confidence (ranging from 0 to 1). Google also accepts audio in some special speex format (audio/x-speex-with-header-byte), which is much smaller in comparison with losless FLAC, but I haven't been able to encode such a sample.

extract email addresses from some file (or any other pattern)

Get your external IP address

Yeah I know it's been up here a million times, but this service is a really clean and nice one. Nothing but your IP address on it. Actually I was to write something like this, and noticed this on appspot... ;)

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands using echo

Commands using echo (1,545) the last day the last week the last month all time sorted by date votes

What's this?

Check These Out

Stay in the loop…

Commands using echo (1,545)

sorted by