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How to stop MAC Address via IPTables

edit the /etc/sysconfig/iptables file and try to work whit this: -A INPUT -i (interface) -m mac (mac address) -j ACCEPT/DROP
This is sample output - yours may be different.
2

-A INPUT -i eth1 -m mac ?mac 00:BB:77:22:33:AA -j ACCEPT

0disse0 · 2010-01-31 15:34:31 6
How to secure delete a file

Instead, install apt-get install secure-delete and you can use: -- srm to delete file and directory on hard disk -- smem to delete file in RAM -- sfill to delete "free space" on hard disk -- sswap to delete all data from swap
This is sample output - yours may be different.
6

shred -u -z -n 17 rubricasegreta.txt

0disse0 · 2010-01-31 15:24:54 6
How to use rysnc over ssh tunnel

Check the ssh_config file and set the variable: StrictHostKeyChecking no
This is sample output - yours may be different.
0

sshpass -p [password] rsync -av -e ssh [utente]@[indirizzoip]:/directorydacopiare/ /directorydidestinazione

0disse0 · 2010-01-31 15:21:14 3
a shell function to print a ruler the width of the terminal window.

A similar version for Bash that doesn't require cut and shortens the function in a few places. And it uses local variables. (similar to a version by eightmillion in a comment on the another version) Show Sample Output
This is sample output - yours may be different.
```
....^....|....^....|....^....|....^....|....^....|....^....|....^....|....^....|
12345678901234567890123456789012345678901234567890123456789012345678901234567890
```
2

ruler() { for s in '....^....|' '1234567890'; do w=${#s}; str=''; for (( i=1; i<=(COLUMNS + w) / $w; i=i+1 )); do str+=$s; done; str=${str:0:COLUMNS} ; echo $str; done; }

dennisw · 2010-01-31 05:55:00 5
grab all commandlinefu shell functions into a single file, suitable for sourcing.

Much simpler but not as many features as the alternative.
This is sample output - yours may be different.
2

curl -s http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-2400:25] | grep -oP "^\w+\ *{.*}"

matthewbauer · 2010-01-31 05:14:11 6

Facebook Email Scraper

(Apparently it is too long so I put it in sample output, I hope that is OK.) Run the long command (or put it in your .bashrc) in sample output then run: fbemailscraper YourFBEmail Password Voila! Your contacts' emails will appear. Facebook seems to have gotten rid of the picture encoding of emails and replaced it with a text based version making it easy to scrape! Needs curl to run and it was made pretty quickly so there might be bugs. Show Sample Output

fbemailscraper YourFBEmail Password

dabom · 2010-01-31 00:44:35 45

View the newest xkcd comic.

Add an alias to your .bashrc that allows you to issue the command xkcd to view (with gwenview) the newest xkcd comic... I know there are thousands of them out there but this one is at least replete with installer and also uses a more concise syntax... plus, gwenview shows you the downloading progress as it downloads the comic and gives you a more full featured viewing experience.
This is sample output - yours may be different.
-5

echo alias xkcd="gwenview `w3m -dump http://xkcd.com/|grep png | awk '{print $5}'` 2> /dev/null" >> .bashrc

GinoMan2440 · 2010-01-30 20:38:16 5
grab all commandlinefu shell functions into a single file, suitable for sourcing.

Each shell function has its own summary line, as a comment. If there are multiple shell functions with the same name, the function with the highest number of votes is put into the file. Note: added 'grep -v' to the end of the pipeline, to eliminate extraneous lines containing only '--'. Thanks to matthewbauer for pointing this out.
This is sample output - yours may be different.
8

export QQ=$(mktemp -d);(cd $QQ; curl -s -O http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-2400:25];for i in $(perl -ne 'print "$1\n" if( /^(\w+)/ )' *|sort -u);do grep -h -m1 -B1 $i *; done)|grep -v '^--' > clf.sh;rm -r $QQ

bartonski · 2010-01-30 19:47:42 40
Set a posix shell to echo all commands that it's about to execute, after all expansions have been done.

the 'set -x' mode can be exited by typing set +x Show Sample Output
This is sample output - yours may be different.
```
$ set -x
$ pwd
+ pwd
/tmp
$ asdf='x*'
+ asdf='x*'
$ cd ~
+ cd /home/tiger
$ find $OLDPWD -name "$asdf"
+ find /tmp -name 'x*'
...
```
3

set -x

bartonski · 2010-01-30 16:08:54 12
Define words and phrases with google.

This version works on Mac (avoids grep -P, adding a sed step instead, and invokes /usr/bin/perl with full path in case you have another one installed). Still requires that you install perl module HTML::Entities ? here's how: http://www.perlmonks.org/?node_id=640489
This is sample output - yours may be different.
7

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Eo '<li>[^<]+'|sed 's/^<li>//g'|nl|/usr/bin/perl -MHTML::Entities -pe 'decode_entities($_)';}

gthb · 2010-01-30 13:08:03 14
Pipe music over netcat with mpg123

I think I picked this one up from Hak5 (yeah I know.. kinda lame)
This is sample output - yours may be different.
-3

#Client# cat "The Meters - People Say.mp3" | nc -vv 192.168.1.100 8080; #Server# nc -vv -l -s 192.168.1.100 -p 8080 | mpg123 -v -

Abiden · 2010-01-30 08:50:17 7
Copy the directory you want to specify a comma separated list of directories to copy.
This is sample output - yours may be different.
0

cp -arv ~/Documents/{foo,bar} --target-directory=~/buzz/

sugitaro · 2010-01-30 08:38:54 7
How to backup hard disk timely?

Creates files in $DATE and hardlinks existing files to $PREVDATE. Thus full backup in each directory. Only drawback is changed modification time. Recommend a wrapper script to determine $DATE and $PREVDATE. Works like a charm. (Dirvish handrolled)
This is sample output - yours may be different.
5

rsync -a --link-dest=/media/backup/$HOSTNAME/$PREVDATE '--exclude=/[ps][ry][os]' --exclude=/media/backup/$HOSTNAME / /media/backup/$HOSTNAME/$DATE/

danam · 2010-01-30 08:36:41 38
Rename duplicates from MusicBrainz Picard

Renames duplicates from MusicBrainz Picard, so you get the latest copy and not a bunch of duplicates. Show Sample Output
This is sample output - yours may be different.
```
`abba/forever_gold_(disc_1__abba_gold)/19-waterloo (1).mp3' -> `abba/forever_gold_(disc_1__abba_gold)/19-waterloo.mp3'
```
1

for i in */*/*$1$*; do mv -f "$i" "${i/ (1)}"; done

magenine · 2010-01-30 03:11:55 3
grep (or anything else) many files with multiprocessor power

Parallel does not suffer from the risk of mixing of output that xargs suffers from. -j+0 will run as many jobs in parallel as you have cores. With parallel you only need -0 (and -print0) if your filenames contain a '\n'. Parallel is from https://savannah.nongnu.org/projects/parallel/
This is sample output - yours may be different.
5

find . -type f | parallel -j+0 grep -i foobar

unixmonkey8046 · 2010-01-30 02:08:46 17
diff the same file in two directories.

This is useful when you're diffing two files of the same name in radically different directory trees. For example: Set path1='/some/long/convoluted/path/to/all/of/your/source/from/a/long/dead/machine' then path2='/local/version/of/same/file' then run the command. Much easier on the eyes when you're looking back across your command history, especially if you're doing the same diff over and over again.
This is sample output - yours may be different.
1

diff {$path1,$path2}/file_to_diff

bartonski · 2010-01-29 23:00:57 3
Mirror every lvol in vg00 in hp-ux 11.31

Create one mirror copy of every lvol in the vg00 just after a cold install of an HP-UX 11.31. Cna be used also for 11.23 but remember that in 11iv2 there is no agile view so the disk will be /dev/dsk/cxtxdxs2
This is sample output - yours may be different.
0

for i in in $(vgdisplay -v vg00 | grep "LV Name" | awk '{ print $3 };'); do; lvextend -m 1 $i /dev/disk/<here-goes-the-disk>; done

jreypo · 2010-01-29 22:43:07 3
Validating a file with checksum
This is sample output - yours may be different.
1

[ "c84fa6b830e38ee8a551df61172d53d7" = "$(md5sum myfile | cut -d' ' -f1)" ] && echo OK || echo FAIL

tuxilicious · 2010-01-29 21:46:26 4
Replace spaces in filenames with underscores

It's the rename-tool from debians perl-package.
This is sample output - yours may be different.
8

rename 's/ /_/g' *

tuxilicious · 2010-01-29 21:15:03 8
Replace spaces in filenames with underscores

I realize there's a few of these out there, but none exactly in this form, which seems the cleanest to me
This is sample output - yours may be different.
9

for f in *;do mv "$f" "${f// /_}";done

ethanmiller · 2010-01-29 19:57:16 9
test moduli file generated for openssh

this command test the moduli file generated by the command ssh-keygen -G /tmp/moduli-2048.candidates -b 2048 . The test can be long depend of your cpu power , around 5 minutes to 30 minutes
This is sample output - yours may be different.
1

ssh-keygen -T moduli-2048 -f /tmp/moduli-2048.candidates

eastwind · 2010-01-29 19:35:21 3
generate the moduli file for openssh if lost

if you lost your moduli file in openssh server side you need generate new one with this command then test if the number generated can be used with ssh-keygen -T moduli-2048 -f /tmp/moduli-2048.candidates
This is sample output - yours may be different.
0

ssh-keygen -G /tmp/moduli-2048.candidates -b 2048

eastwind · 2010-01-29 19:33:23 3
Validating a file with checksum

Makes sure the contents of "myfile" are the same contents that the author intended given the author's md5 hash of that file ("c84fa6b830e38ee8a551df61172d53d7").
This is sample output - yours may be different.
2

md5 myfile | awk '{print $4}' | diff <(echo "c84fa6b830e38ee8a551df61172d53d7") -

voidpointer · 2010-01-29 16:57:13 6
Netcat Relay

This is an example of using 3 hosts, in a netcat relay. first host connects to middle host 1 -> 2 Second hosts redirects to target host 1 -> 2 -> 3 I hope this makes sense.
This is sample output - yours may be different.
2

nc -vv $MIDDLEHOST 1234; ## nc -vv -l $IamMIDDLEHOST 1234 | nc $Targethost 1234;## nc -l $IamTargetHost 1234 -e /bin/bash;

Abiden · 2010-01-29 16:45:39 140
Triangular Number
This is sample output - yours may be different.
0

echo $(echo $(seq $MIN $MAX) | sed 's/ /+/g') | bc -l

Abiden · 2010-01-29 16:41:07 3
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What's this?

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Binary digits Matrix effect

Silly Perl variant.

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

List your largest installed packages (on Debian/Ubuntu)

The other commands were good, but they included packages that were installed and then removed. This command only shows packages that are currently installed, sorts smallest to largest, and formats the sizes to be human readable.

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.

Printout a list of field numbers (awk index) from a CSV file with headers as first line.

Useful to identify the field number in big CSV files with large number of fields. The index is the reference to use in processing with commands like 'cut' or 'awk' involved.

Benchmark SQL Query

Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

Poor man's nmap for a class C network from rfc1918

What do you do when nmap is not available and you want to see the hosts responding to an icmp echo request ? This one-liner will print all hosts responding with their ipv4 address.

Determine space taken by files of certain type

Just how much space are those zillions of database logs taking up ? How much will you gain on a compression rate of say 80% ? This little line gives you a good start for your calculations.

Find all dot files and directories

Compare two CSV files, discarding any repeated lines

The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

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