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2011-03-12 - Confoo 2011 presentation
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kill_daemon() { echo "Daemon?"; read dm; kill -15 $(netstat -atulpe | grep $dm | cut -d '/' -f1 | awk '{print $9}') }; alias kd='kill_daemon
2009-05-26 20:39:56
User: P17
Functions: alias awk cut echo grep kill netstat read
Tags: alias kill netstat
-5
Up
Down
Kill a daemon by name, not by PID

Just find out the daemon with $ netstat -atulpe. Then type in his name and he gets the SIGTERM.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dpkg-query -W | grep perl
2010-07-20 16:14:04
User: unixmonkey10924
Functions: grep
-5
Up
Down
Print a list of installed Perl modules

IMVHO if you are using cpan to install perl modules you are doing it wrong.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
FOR /f %%g in ('echo %1 ^| iconv -f gbk -t utf-8') DO curl -x proxy:port -u user:pass -d status=%%g -d source="cURL" http://twitter.com/statuses/update.xml
2010-07-21 04:53:54
User: MeaCulpa
Functions: iconv
Tags: windows curl iconv
-5
Up
Down
Post to twitter via curl, Windows version

Aside from curl one will need iconv windows binary since windows lacks a native utf-8 cli interface. In my case I need a proxy in China and iconv to convert gbk status string into utf-8. GnuWin32 is a good choice with loads of coreutils natively ported to Windows

"FOR /f" is the solution to pass iconv output to curl.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
Printing portion of a big file
2009-03-30 11:08:38
User: acirulli
Tags: sed
-5
Up
Down
sed -n "$LINE1,${LINE2}p;${LINEA2}q;" "$FILE"

If you need to print some portion of a huge file, let's say you want to print from line 200 to 300, you can use this command to print the line from LINE1 to LINE2 of file FILE.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
shred -v filename
2013-05-07 14:58:17
User: techie
Functions: shred
-5
Up
Down
Delete a file securely by overwriting its contents
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/urandom of=/dev/speaker bs=1
2010-10-27 09:22:40
User: khashmeshab
Functions: dd
Tags: speaker beep random
-5
Up
Down
Random Beeps on Your PC Speaker

Sends random beeps to your PC-speaker. Think... You can also run it remotely on another computer using SSH and scare its user! Don't forget to run it on your dedicated hosting server and watch sysadmin's action from data-center's live remote cameras!

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk 'END {print NR}' /etc/passwd
2011-06-23 00:33:40
User: Leo_Gutierrez
Functions: awk
-5
Up
Down
How many lines does the passwd file have?
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
dd if=/dev/urandom of=/dev/dsp
2010-10-27 09:25:02
User: khashmeshab
Functions: dd
Tags: speaker beep sound random
-5
Up
Down
Random Beeps on Your Audio Card's Output

Sends random sounds to your sound card output (e.g. your speaker). Think... You can also run it remotely on another computer using SSH and scare its user!

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo 1+1|bc
2009-02-19 13:46:58
User: gnawa
Functions: echo
-5
Up
Down
doing some math...
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
export var1=`ps -A | grep '[u]nique' | cut -d '?' -f 1`; echo${var1/ /}; kill -9 $var1
2010-03-22 21:06:58
User: headyadmin
Functions: cut export grep kill
Tags: Os X
-5
Up
Down
Kill process you don't know the PID of, when pidof and pgrep are not available.

This will kill a specific process you don't know the PID of, when pidof and pgrep are not available, for example on OS X. var1 is created so that the whitespace can be trimmed before passing off to kill.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
join file1.txt file2.txt > file3.txt
2009-03-01 05:12:07
User: olafrv
Functions: join
-6
Up
Down
Concatenate lines of to files, one by one
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
apt-get search something | grep specific
2010-09-27 07:10:39
User: ProfOak
Functions: apt grep
-6
Up
Down
Refined repository search

replace apt-get with your distro's package manager.

Where 'something' is the package name, and 'specific' is what you're specifically looking for.

This helps if your query is 2+ words long.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
grep -A 3 -i "example" demo_text
2013-05-09 08:20:31
User: techie
Functions: grep
Tags: grep
-6
Up
Down
Print the matched line, along with the 3 lines after it.
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
python -c "import socket; print '\n'.join(socket.gethostbyname_ex(socket.gethostname())[2])"
2009-04-30 16:10:43
User: haivu
Functions: python
Tags: Network python
-6
Up
Down
One-Liner to Display IP Addresses

The socket.gethostname() call returns the host name of the computer. The socket.gethostbyname_ex() call returns a list of three items: The host name, the list of aliases for this host, and a list of IP addresses. Recall that Python?s array starts with index 0, the socket.gethostbyname_ex(?)[2] expression refers to the list of IP addresses. Finally, the print statement prints out the IP addresses, one per line.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl whatismyip.org
2011-10-15 12:22:34
User: mathias
-6
Up
Down
What is my IP address?
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
vim -R /etc/passwd
2013-05-09 08:28:32
User: techie
Functions: vim
Tags: vim
-6
Up
Down
Open a file using vim in read only (like less)
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
nawk '{line[NR]=$0} END{for (; NR>=1; NR--){print line[NR]}}' FILENAME
2009-03-20 12:43:31
User: lme
-6
Up
Down
reverse-print contents of a file
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sudo dmesg
2009-08-19 11:06:05
User: theIndianMaiden
Functions: sudo
Tags: system_profiler
-6
Up
Down
detected hardware and boot messages
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for i in $(file * | grep broken | cut -d : -f 1); do rm $i; done
2010-11-02 16:10:42
User: Znuff
Functions: cut file grep rm
-6
Up
Down
remove all dead symbolic links in a directory
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
scp -P 22 /home/svnlabs.txt root@92.178.0.56:/home/svnlabs.txt
2010-01-22 16:55:25
User: svnlabs
Functions: scp
-6
Up
Down
Upload file to remote server using SCP

Upload file to remote server using SCP

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
telnet zerocarbs.wooters.us
2010-06-26 05:50:48
User: wickedcpj
Functions: telnet
-6
Up
Down
Connects to a telnet service monitoring Woot!

Gives you an updating woot! item tracker!

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
scp /home/svnlabs.txt root@92.178.0.56:/home/
2010-01-22 21:19:37
User: bakhru
Functions: scp
Tags: a2zfa file cop
-6
Up
Down
Upload file to remote server using SCP
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find ~/Desktop/ \( -regex '.*/\..*' \) -print -exec rm -Rf {} \;
2009-06-02 19:45:06
User: unixmonkey4063
Functions: find rm
Tags: hidden find
-6
Up
Down
Search for all files that begin with . and delete them.
Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
watch -n 1 uptime\;myqladmin --user=<user> --password=<password> --verbose processlist
2009-03-21 18:29:28
User: root
Functions: watch
Tags: mysql
-6
Up
Down
Monitor server load as well as running MySQL processes

Useful for monitoring both MySQL and the server load at the same time.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps -ef | grep [j]boss | awk '{print $2}'|xargs kill -9
2010-09-30 15:55:41
User: utoxin
Functions: awk grep kill ps xargs
Tags: kill
-6
Up
Down
Kill any process with one command using program name

Removed unneeded grep -v by making the initial grep unable to match itself.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate