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awk, bash, curl, find, grep, Linux, sed
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Functions

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Terminal - All commands - 12,453 results
sed 'X{N;s/\n//;}' file.txt (where X is the current line)
2016-07-30 14:27:20
User: pibarnas
Functions: sed
2
Up
Down
Embed next line on the end of current line using sed

N: On the current line, sed will display it on pattern space, plus a \n (new line); but

s/\n//: Will get rid of new line displayed on pattern space, joining the current line's end with the start of the next line

Useful in scripts.

Show sample output | Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
links `lynx -dump -listonly "http://news.google.com" | grep -Eo "(http|https)://[a-zA-Z0-9./?=_-]*" | grep -v "google.com" | sort -R | uniq | head -n1`
2016-07-26 12:54:53
User: mogoh
Functions: grep head sort uniq
Tags: firefox internet browser random google News
1
Up
Down
Read random news on the internet

sort -R randomize the list.

head -n1 takes the first.

Comments (11) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
links $( a=( $( lynx -dump -listonly "http://news.google.com" | grep -Eo "(http|https)://[a-zA-Z0-9./?=_-]*" | grep -v "google.com" | sort | uniq ) ) ; amax=${#a[@]} ; n=$(( `date '+%s'` % $amax )) ; echo ${a[n]} )
2016-07-26 11:52:12
User: pascalv
Functions: echo grep sort uniq
Tags: firefox internet browser random google News
2
Up
Down
Read random news on the internet

Access a random news web page on the internet.

The Links browser can of course be replaced by Firefox or any modern graphical web browser.

Comments (21) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
!!:s/foo/bar/
2016-07-25 18:52:42
User: malathion
3
Up
Down
Runs previous command but replacing

Replaces the first instance of 'foo' with 'bar'. To replace all instances of 'foo' with 'bar': !!:gs/foo/bar/

Comments (14) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
f=correlation.png; s=400; t=50; a=1.2; convert $f -resize ${s}% -threshold ${t}% bmp:- | potrace -o ${f%.*}.svg -b svg -z black --fillcolor "#FFFFFF" --alphamax ${a}
2016-07-25 10:45:28
User: T4b
1
Up
Down
Vectorize xkcd strips

Uses ImageMagick and potrace to vectorize the input image, with parameters optimized for xkcd-like pictures.

Comments (15) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while true ; do wget --quiet --no-check-certificate --post-data 'login=my_account_number&password=my_password&submit=Valider' 'https://wifi.free.fr/Auth' -O '/dev/null' ; sleep 600; done
2016-07-23 16:34:42
User: pascalv
Functions: sleep true wget
Tags: wifi France
2
Up
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Connect to FreeWifi hotspot (France) and keep the connection active

(In French) Connection aux hotspots FreeWifi, et maintien de la connection active

Comments (11) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
hpacucli controller all show config detail | grep -A 7 Fail | egrep '(Failed|Last|Serial Number|physicaldrive)'
2016-07-20 17:42:40
User: operat0r
Functions: egrep grep
1
Up
Down
Get the serial numbers from HP RAID

This dumps serial numbers of all the drives but HP warranty check does not say they are valid ...

Show sample output | Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tree -i -L 1
2016-07-11 18:48:21
User: antonangeli
Tags: find group
2
Up
Down
lists files and folders in a folder

lists files and folders in a folder with summary.

Show sample output | Comments (12) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl -s http://whatismyip.org/ | grep -oP '(\d{1,3}\.){3}\d+'
2016-07-11 18:07:37
User: ciekawy
Functions: grep
Tags: curl ip address
3
Up
Down
Get your outgoing IP address
Comments (10) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lsa() { ls -lart; history -s "joe \"$(\ls -apt|grep -v /|head -1)\"" ; }
2016-07-07 21:27:55
User: knoppix5
Functions: ls
3
Up
Down
access to last touched or created file with arrow_up_key immediately after displaying the file list

Display recursive file list (newest file displayed at the end) and be free to access last file in the list simply by pressing arrow_up_key i.e. open it with joe editor.

BTW IMHO the list of files with newest files at the end is often more informative.

Put this 'lsa' function somewhere in your .bashrc and issue

. ~/.bashrc

or

source ~/.bashrc

to have access to the 'lsa' command immediately.

.

(the function appends command "joe last_file_in_the_list" at the end of command history)

Comments (10) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while true; do A=$(stat -c%s FILE); sleep 1; B=$(stat -c%s FILE); echo -en "\r"$(($B-$A))" Bps"; done
2016-06-27 20:39:06
User: Zort
Functions: echo sleep stat
-2
Up
Down
Muestra el crecimiento de un archivo por segundo

Muestra el crecimiento de un archivo por segundo.

Cambia el texto "FILE" por el nombre del archivo a monitorear.

Comando STAT

Comments (31) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while true; do A=$(ls -l FILE | awk '{print $5}'); sleep 1; B=$(ls -l FILE | awk '{print $5}'); echo -en "\r"$(($B-$A))" Bps"; done
2016-06-27 20:33:02
User: Zort
Functions: awk echo ls sleep
-3
Up
Down
Muestra el crecimiento de un archivo por segundo

Muestra el crecimiento de un archivo por segundo.

Cambia el texto "FILE" por el nombre del archivo a monitorear.

Comando LS + AWK

Show sample output | Comments (11) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
netstat -n | grep ESTAB |grep :80 | tee /dev/stderr | wc -l
2016-06-26 11:37:19
User: rubenmoran
Functions: grep netstat tee wc
3
Up
Down
Two command output

Summarize established connections after netstat output.

Using tee and /dev/stderr you can send one command output to terminal before executing wc so you can summarize at the bottom of the output.

Show sample output | Comments (13) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sed '/INSERT INTO `unwanted_table`/d' mydb.sql > reduced.sql
2016-06-24 20:13:47
User: sudopeople
Functions: sed
Tags: mysql mysqldump mysql import
1
Up
Down
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.

Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
less -X /var/log/insecure
2016-06-24 13:53:49
User: sonic
Functions: less
2
Up
Down
Do not clear the screen after viewing a file with less

From the manpage:

man less

-X or --no-init

Disables sending the termcap initialization and deinitialization strings to the terminal. This is sometimes desirable if the deinitialization string does something unnecessary, like clearing the screen.

Bonus:

If you want to clear the screen after viewing a file this way that had sensitive information, hit or just type clear. Since is readily available, I don't know why less bothers to automatically clear. If you're viewing the file at all, chances are you want to see the output from it after you quit.

Show sample output | Comments (14) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo '"\e\C-i": "\C-awhile true; do ( \C-e ); inotifywait -q -e modify -e close_write *; done\e51\C-b"' >>~/.inputrc
2016-06-10 08:06:50
User: unhammer
Functions: echo
Tags: edit readline inotify inotifywait compile inputrc
1
Up
Down
.inputrc keybinding to wrap current line in inotifytools for instant compile/test-as-you-save-loop

Assuming you've written all of

make -j hfst-tokenize && echo doavtter gr?dakursa|./hfst-tokenize --gtd tokeniser-gramcheck-gt-desc.pmhfst

and want that to execute every time you :w in vim (or C-xC-s in Emacs), just hit and it'll turn into

while true; do ( make -j hfst-tokenize && e doavtter gr?dakursa|./hfst-tokenize --gtd tokeniser-gramcheck-gt-desc.pmhfst ); inotifywait -q -e modify -e close_write *; done

with the cursor right before the ')'. Hit enter, and it'll run on each save.

Requires the package inotify-tools installed.

Show sample output | Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "https://www.google.com/maps/place/$(exiftool -ee -p '$gpslatitude, $gpslongitude' -c "%d?%d'%.2f"\" image.jpg 2> /dev/null | sed -e "s/ //g")"
2016-06-09 13:33:10
User: mpb
Functions: echo
3
Up
Down
Generate a Google maps URL for GPS location data from digital photo

This command uses the "exiftool" command which is available here: http://www.sno.phy.queensu.ca/~phil/exiftool/

NB, there should be a degree symbol right after the first "%d" NOT a question mark.

For some unknown reason, commandlinefu is not able to handle degree symbol correctly ("?")?

Show sample output | Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
rsync -a --delete empty-dir/ target-dir/
2016-06-07 16:56:55
User: malathion
Functions: rsync
Tags: delete rsync
10
Up
Down
Optimal way of deleting huge numbers of files

This command works by rsyncing the target directory (containing the files you want to delete) with an empty directory. The '--delete' switch instructs rsync to remove files that are not present in the source directory. Since there are no files there, all the files will be deleted.

I'm not clear on why it's faster than 'find -delete', but it is.

Benchmarks here: https://web.archive.org/web/20130929001850/http://linuxnote.net/jianingy/en/linux/a-fast-way-to-remove-huge-number-of-files.html

Comments (89) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sudo mount -o remount,rw / && sudo cp /etc/hosts /etc/hosts.old && wget http://winhelp2002.mvps.org/hosts.txt && cp /etc/hosts ~/ && cat hosts.txt >> hosts && sudo cp hosts /etc/hosts
2016-06-06 15:01:19
User: bugmenot
Functions: cat cp mount sudo wget
Tags: hosts ubuntu-phone ubuntu touch
2
Up
Down
Ad blocking on Ubuntu phone/tablet with hosts file

Will append lines to the hosts file to do some basic ad blocking.

Comments (12) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl --silent --head "${url}" | grep 'Last-Modified:' | cut -c 16- | date -f - +'%s'
2016-06-02 22:20:55
User: odoepner
Functions: cut date grep
Tags: last, modfiied curl url
1
Up
Down
Retrieve "last modified" timestamp of web resource in UTC seconds

This command line assumes that "${url}" is the URL of the web resource.

It can be useful to check the "freshness" of a download URL before a GET request.

Show sample output | Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl http://url/rss | grep -o '<enclosure url="[^"]*' | grep -o '[^"]*$' | xargs wget -c
2016-05-29 12:07:21
User: dakira
Functions: grep wget xargs
Tags: bash xargs wget grep xml rss podcast
1
Up
Down
Download all files from podcast RSS feed

Neither of the others worked for me. This does.

Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tree -isafF /var|grep -v "/$"|tr '[]' ' '|sort -k1nr|head
2016-05-27 16:41:20
User: knoppix5
Functions: grep sort tr
4
Up
Down
Find top 10 largest files in /var directory (subdirectories and hidden files included )

Should work even when very large files exist.

Comments (20) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
du -a /var | sort -n -r | head -n 10
2016-05-27 04:05:08
User: zluyuer
Functions: du head sort
1
Up
Down
Find top 10 largest files
Comments (14) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo "$USER"|rev | espeak
2016-05-26 16:10:20
User: bugmenot
Functions: echo rev
Tags: backwards name
4
Up
Down
Your name backwards
Comments (13) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps -u jboss -o nlwp= | awk '{ num_threads += $1 } END { print num_threads }'
2016-05-23 08:41:47
User: leonbartlett
Functions: awk ps
Tags: threads
0
Up
Down
Thread count per user
Comments (11) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate