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Extract all urls from the last firefox sessionstore.js file used.
This is sample output - yours may be different.
-1

sed -e 's/{"url":/\n&/g' ~/.mozilla/firefox/*/sessionstore.js | cut -d\" -f4

cfajohnson · 2009-12-10 04:31:31 4
Change the homepage of Chromium
This is sample output - yours may be different.
-1

change-homepage(){ sed -ri 's|( "homepage": ").*(",)|\1'"$@"'\2|' .config/chromium/Default/Preferences; }

matthewbauer · 2010-04-10 21:21:55 3
Add EC2 pem key to SSH

This command adds your pem key to SSH so that you no longer have to manually specify it when connecting to EC2 instances. # you can do this: ssh ec2-instance.amazonaws.com # instead of this: ssh -i ~/.ssh/KEY_PAIR_NAME.pem ec2-instance.amazonaws.com Show Sample Output
This is sample output - yours may be different.
```
Identity added: /Users/johndoe/.ssh/KEY_PAIR_NAME.pem (/Users/johndoe/.ssh/KEY_PAIR_NAME.pem)
```
-1

ssh-add ~/.ssh/KEY_PAIR_NAME.pem

brockangelo · 2012-11-03 02:59:52 5
Creating rapidly an html menu

This will create rapidly an html menu. You can paste it in you're html page with the middle button(the wheel). I didn't test it in an html with css, but it seems alright. Show Sample Output
This is sample output - yours may be different.
```
<ul>
 <li>menu 1</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
<ul>
 <li>menu 2</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
<ul>
 <li>menu 3</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
<ul>
 <li>menu 4</li>
  <ul>
   <li>item 1</li>
   <li>item 2</li>
   <li>item 3</li>
   <li>item 4</li>
   <li>item 5</li>
  </ul>
</ul>
```
-1

for menu in {1..4}; do echo -e "<ul>\n <li>menu $menu</li>\n <ul>"; for items in {1..5}; do echo " <li>item $items</li>"; if [ $items -eq 5 ];then echo -e " </ul>";fi;done; echo "</ul>";done | xclip

qcjn · 2013-09-22 06:34:32 6
List complete size of directories (do not consider hidden directories)
This is sample output - yours may be different.
-1

du --max-depth=1 | grep -v '\.\/\.'

netkavu · 2010-04-10 22:14:49 3
find names of files ending in *log that have both foo and bar

Uses xargs to call the second grep with the first grep's results as arguments
This is sample output - yours may be different.
-1

grep -l bar *.log | xargs grep -l foo

dlebauer · 2011-01-10 19:54:46 3
Convert DOS newlines (CR/LF) to Unix format

requires the package tofrodos on Debian/Ubuntu: sudo apt-get install tofrodos
This is sample output - yours may be different.
-1

fromdos <file>

jbuitt · 2011-02-14 17:28:53 3
measure answer time of a web service

This uses curl to find out the access times of a web service Show Sample Output
This is sample output - yours may be different.
```
1. 13:54:15: real 0m0.393s
2. 13:54:21: real 0m0.053s
3. 13:54:28: real 0m0.678s
4. 13:54:34: real 0m0.166s
....
40. ...
```
-1

for i in {1..40};do echo -n $i. $(date +%H:%M:%S):\ ; (time curl 'http://ya.ru/' &> /dev/null) 2>&1|grep real;sleep 1;done

AntonyC · 2011-11-11 10:40:38 3
Change all instances of a word in all files in the current directory

This command will replace all instances of 'foo' with 'bar' in all files in the current working directory.
This is sample output - yours may be different.
-1

perl -pi -e 's/foo/bar/g' $(grep -l foo ./*)

dopeman · 2009-03-27 17:18:08 6
Generate a Universally Unique Identifier (UUID)

http://en.wikipedia.org/wiki/Universally_Unique_Identifier http://www.ossp.org/pkg/lib/uuid/ You'll first need to install the uuid package. Available immediately from apt in Ubuntu, Debian, or other myriad Debian variants. You could always compile it from source as well. Show Sample Output
This is sample output - yours may be different.
```
bfcca18a-8857-11de-bdc3-0024e80e2d83
```
-1

uuid

linuxrawkstar · 2009-08-14 14:02:37 7
List complete size of directories (do not consider hidden directories)
This is sample output - yours may be different.
-1

du -sh * | grep -v '\.\/\.'

marcopferreira · 2010-04-10 23:19:46 4
Get Informed by your box that you are awesome ;)

sends notification msg within repeated intervals of time to notify-send ;) Just for fun.
This is sample output - yours may be different.
-1

while $i;do `notify-send -t 200 "You are awesome :)"`;sleep 60; done;

pahnin · 2011-02-14 18:49:38 7
Clear Cached Memory on Ubuntu

"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
This is sample output - yours may be different.
-1

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

StephenJudge · 2012-03-17 08:27:58 13
Useful to check if the disks as of same size or not. Helpful in checking Raid configs
This is sample output - yours may be different.
-1

df | awk '{if ($2!=dspace) print "different"; dspace=$2;}'

adimania · 2013-03-08 12:09:35 14
purge half of files in backup directory

If you have a directory with lot of backups (full backups I mean), when it gets to some size, you could want to empty some space. With this command you'll remove half of the files. The command assumes that your backup files starts with YYYYMMDD or that they go some alphabetical order. Show Sample Output
This is sample output - yours may be different.
```
(nothing, it will remove half of the files)
```
-1

find . | sort | awk 'NR%2==0' | xargs rm $1

sucotronic · 2013-07-11 07:36:18 10
Shuffle mp3 files in current folder (and subfolders) and play them.

Add `-maxdepth 1` to find to exclude subfolders.
This is sample output - yours may be different.
-1

find . -iname "*.mp3" | mpg123 -Z --list -

bjodah · 2013-12-16 14:07:59 9
Change all instances of a word in all files in the current directory and it's sub-directories

This command will replace all instances of 'foo' with 'bar' in all files in the current working directory and any sub-directories.
This is sample output - yours may be different.
-1

perl -pi -e 's/foo/bar/g' $(grep -rl foo ./*)

dopeman · 2009-03-27 17:21:35 10
For finding out if something is listening on a port and if so what the daemon is.
This is sample output - yours may be different.
-1

lsfo -i :[port number]

unixmonkey11400 · 2010-08-17 19:25:37 3
Get your external IP address

Additionally it may give your geolocation if it's known by hostip.info Show Sample Output
This is sample output - yours may be different.
```
ipv4: 188.165.241.33
hostname: ns390090.ovh.net
city: Roubaix
country: FRANCE (FR)
latitude: 50.7
longitude: 3.1667
```
-1

curl http://my-ip.cc/host.txt

samleb · 2011-09-01 00:28:49 3
find all minimum values in file with at least 100 lines
This is sample output - yours may be different.
-1

for ff in directory; do numLines=`wc -l $ff`; numLines=$(echo $numLines | sed 's/ .*//g'); min=$(sort -nrk 1 $ff | tail -1); if [ $numLines -gt 100 ]; then echo $min >> minValues; fi;done;

user1234 · 2013-09-23 04:04:52 7
return external ip

alternative using 'host' Show Sample Output
This is sample output - yours may be different.
```
67.207.139.81
```
-1

host -t a dartsclink.com | sed 's/.*has address //'

dartsclink · 2009-08-14 16:11:18 13
List complete size of directories (do not consider hidden directories)
This is sample output - yours may be different.
-1

du -sh `ls -p | grep /`

sarcilav · 2010-04-11 02:53:51 11

Get your external IP address

XML version. Additionally it may give your geolocation if it's known by hostip.info Show Sample Output

-1

curl http://my-ip.cc/host.xml

samleb · 2011-09-01 00:30:03 3

Keep gz file after uncompressing
This is sample output - yours may be different.
-1

gunzip -c x.txt.gz >x.txt

zluyuer · 2014-10-24 10:00:21 10
display IP addresses with 5 or more unsuccessful login attempts today

display IP's that unsuccessfully attempted to login 5 or more times today may want to filter any trusted IP's and the localhost useful for obtaining a list IP addresses to block on the firewall Show Sample Output
This is sample output - yours may be different.
```
the output is zero or more IP addresses
```
-1

lastb -i | grep "$(date '+%a %b %d')" | awk '{ print $3 }' | sort | uniq -c | awk '{ if ($1 >= 5) print $2; }'

forestb · 2015-11-20 07:19:20 10
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Use tee to process a pipe with two or more processes

Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

run command on a group of nodes in parallel redirecting outputs

Do the same as pssh, just in shell syntax. Put your hosts in hostlist, one per line. Command outputs are gathered in output and error directories.

Display the standard deviation of a column of numbers with awk

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Top ten (or whatever) memory utilizing processes (with children aggregate)

This command loops over all of the processes in a system and creates an associative array in awk with the process name as the key and the sum of the RSS as the value. The associative array has the effect of summing a parent process and all of it's children. It then prints the top ten processes sorted by size.

Find last 50 modified files

Install a basic FreeBSD system

Install a basic FreeBSD system on a distant server. I use this to install FreeBSD on servers that can only boot a Linux rescue system. This sytem loads on ram when booted, so it is possible to install freely. You can even install on ZFS root !

Found how how much memory in kB $PID is occupying in Linux

The "proportional set size" is probably the closest representation of how much active memory a process is using in the Linux virtual memory stack. This number should also closely represent the %mem found in ps(1), htop(1), and other utilities.

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