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Find removed files still in use via /proc

Oracle DBA remove some logfiles which are still open by the database and he is complaining the space has not been reclaimed? Use the above command to find out what PID needs to be stopped. Or alternatively recover the file via: cp /proc/pid/fd/filehandle /new/file.txt Show Sample Output

find -L /proc/*/fd -links 0 2>/dev/null

res0nat0r · 2009-06-26 18:42:51 12

Show your account and windows policy settings with Results of Policy msc.

Type this into windows via run and it will display to you your complete policy for windows. This includes group policy, security policy and your active directory account (min password etc).... www.fir3net.com
This is sample output - yours may be different.
4

rsop.msc

felix001 · 2009-06-26 11:19:50 13

Monitor RX/TX packets and any subsquent errors

www.fir3net.com Show Sample Output

watch 'netstat -aniv'

felix001 · 2009-06-26 11:16:42 8

Most simple way to get a list of open ports
This is sample output - yours may be different.
3

netstat -lnp

unixmonkey4415 · 2009-06-26 08:33:03 8
Check processes runed not by you
This is sample output - yours may be different.
-4

ps aux | grep -v `whoami`

unixmonkey4415 · 2009-06-26 08:28:06 8
Merge several pdf files into a single file
This is sample output - yours may be different.
3

pdftk $* cat output $merged.pdf

svg · 2009-06-26 07:36:02 11
bash or tcsh redirect both to stdout and to a file

When plumbers use pipes, they sometimes need a T-joint. The Unix equivalent to this is 'tee'. The -a flag tells 'tee' to append to the file, rather than clobbering it. Tested on bash and tcsh. Show Sample Output
This is sample output - yours may be different.
```
$ echo "Hello World." | tee -a hello.txt
Hello World.
$ cat hello.txt
Hello World.
```
1

echo "Hello World." | tee -a hello.txt

thebillywayne · 2009-06-26 00:55:59 9
Print multiline text starting and ending at specific regexps with perl

Using perl, here, we grep the man page of fetchmail to find the paragraph starting with '-k | --keep' and ending before the paragraph starting with '-K | --nokeep' Show Sample Output
This is sample output - yours may be different.
```
-k | --keep
              (Keyword:  keep)  Keep  retrieved messages on the remote mailserver.  Normally, messages are deleted from the folder on the mailserver after they have been retrieved.  Specifying
              the keep option causes retrieved messages to remain in your folder on the mailserver.  This option does not work with ETRN or ODMR. If used with POP3, it is recommended  to  also
              specify the --uidl option or uidl keyword.

       
```
0

man fetchmail | perl -ne 'undef $/; print $1 if m/^.*?(-k \| --keep.*)-K \| --nokeep.*$/smg'

unixmonkey4437 · 2009-06-25 23:51:35 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
Set an alarm to wake up

Sleep 5h and plays the song as a wake up alarm
This is sample output - yours may be different.
3

sleep 5h && rhythmbox path/to/song

becomingGuru · 2009-06-25 19:15:19 12
Merge several pdf files into a single file

merge a.pdf b.pdf and c.pdf and create ./out.pdf
This is sample output - yours may be different.
5

gs -q -sPAPERSIZE=a4 -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=out.pdf a.pdf b.pdf c.pdf

becomingGuru · 2009-06-25 19:04:28 14
Get a shell with a not available account

Show Sample Output
This is sample output - yours may be different.
```
[root@XXX ~]# su - nobody
This account is currently not available.
[root@XXX ~]# su - nobody -s /bin/sh -c "/bin/sh"
sh-3.2$ id
uid=99(nobody) gid=99(nobody) grupos=99(nobody) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
```
3

su - <user> -s /bin/sh -c "/bin/sh"

nablas · 2009-06-25 15:36:04 12
Scan Network for Rogue APs.

I've used this scan to sucessfully find many rogue APs on a very, very large network. Show Sample Output
This is sample output - yours may be different.
```
Outputs data in greppable format, plain text and XML. The XML output has an associated XSL stylesheet, which allows you to open the data in a browser. 
```
7

nmap -A -p1-85,113,443,8080-8100 -T4 --min-hostgroup 50 --max-rtt-timeout 2000 --initial-rtt-timeout 300 --max-retries 3 --host-timeout 20m --max-scan-delay 1000 -oA wapscan 10.0.0.0/8

merkmerc · 2009-06-25 14:12:26 8
Open a Remote Desktop (RDP) session with a custom resolution.

Using a widescreen monitor, I often get annoyed that the RDP window is too high, or too narrow for what I want to display. In this example, I'm on a 1680 x 1050 display.
This is sample output - yours may be different.
1

mstsc /w:1500 /h:900 /v:www.example.com

merkmerc · 2009-06-25 14:01:42 9

get linkspeed, ip-adress, mac-address and processor type from osx

get desired info from machine and pipe it txt file. Show Sample Output

-2

echo "-------------" >> nicinfo.txt; echo "computer name x" >> nicinfo.txt; ifconfig | grep status >> nicinfo.txt; ifconfig | grep inet >> nicinfo.txt; ifconfig | grep ether >> nicinfo.txt; hostinfo | grep type >> nicinfo.txt;

miccaman · 2009-06-25 12:32:37 31

Disable graphical login on Solaris

With a full installation of Solaris 10, the graphical login and desktop will start by default. This command will disable that feature. To enable it again use: /usr/dt/bin/dtconfig -e Show Sample Output
This is sample output - yours may be different.
```
done 
desktop auto-start disabled. 
```
1

/usr/dt/bin/dtconfig -d

thesuperjason · 2009-06-25 09:32:37 8
Adobe Updater Crashes on Mac OS X Fix

adobe updater keeps popping up. (normal update fails, probably due to insufficient rights) (src: http://aricsblog.blogspot.com/2007/12/adobe-updater-crashes-on-mac-os-x-and.html)
This is sample output - yours may be different.
-9

sudo /Applications/Utilities/Adobe\ Utilities.localized/Adobe\ Updater5/Adobe\ Updater.app/Contents/MacOS/Adobe\ Updater

miccaman · 2009-06-25 08:07:47 18
Search command history on bash

Very handy and time-saving. Do a 'ctrl+ r' on command prompt. You will see a "(reverse-i-search)`':" mark. Just type any sub-string of the command you want to search(provided you have used it sometime in the same session). Keep on searching by repeatedly pressing ctrl+r. Press enter once you get the desired command string. Show Sample Output
This is sample output - yours may be different.
```
blue] $
(reverse-i-search)`': ls

#Press enter to run the selected command.
```
9

ctrl + r

Bluehive · 2009-06-25 06:51:38 12
Update dyndns.org with your external IP.

This is great if you are behind a router that does not support dynamic dns updates! Example: AT&T u-verse gateway... Put this in a script and run it as a cron job.
This is sample output - yours may be different.
5

curl -v -k -u user:password "https://members.dyndns.org/nic/update?hostname=<your_domain_name_here>&myip=$(curl -s http://checkip.dyndns.org | sed 's/[a-zA-Z<>/ :]//g')&wildcard=NOCHG&mx=NOCHG&backmx=NOCHG"

din7 · 2009-06-24 17:00:15 15
Sort a list of numbers on on line, separated by spaces.

You can replace "sort -nu" with "sort -u" for a word list sorted or "sort -R" for a random-sorted line (edit: corrected) Show Sample Output
This is sample output - yours may be different.
```
$ echo "4 2  3 5  2 52  11" | sed "s/$ \|$$/\n/g" | sort -nu | tr "\n" " "| sed -e "s/^ *//" -e "s/ $//"
2 3 4 5 11 52
```
-1

echo $numbers | sed "s/$ \|$$/\n/g" | sort -nu | tr "\n" " " | sed -e "s/^ *//" -e "s/ $//"

chickenzilla · 2009-06-24 15:12:17 7
Check if network cable is plugged in and working correctly

with 'mii-tool -w eth0' you can watch the interface for changes of the link status Show Sample Output
This is sample output - yours may be different.
```
eth0: negotiated 100baseTx-FD, link ok
```
6

mii-tool eth0

flart · 2009-06-24 08:43:55 11
String Capitalization

Helpful when we want to do mass file renaming(especially mp3s). Show Sample Output
This is sample output - yours may be different.
```
$ (STRING="COmManDLinEfU"; echo "${STRING}" | tr '[A-Z]' '[a-z]' | awk '{print toupper(substr($0,1,1))substr($0,2);}')
Commandlinefu
```
0

echo "${STRING}" | tr '[A-Z]' '[a-z]' | awk '{print toupper(substr($0,1,1))substr($0,2);}'

mohan43u · 2009-06-23 21:11:34 119
Size(k) of directories(Biggest first)

somewhat faster version to see the size of our directories. Size will be in Kilo Bytes. to view smallest first change '-k1nr' to '-k1n'.
This is sample output - yours may be different.
4

find . -depth -type d -exec du -s {} \; | sort -k1nr

mohan43u · 2009-06-23 20:52:35 11
Get the canonical, absolute path given a relative and/or noncanonical path

readlink -f accepts a relative, noncanonical path and emits the corresponding canonical, absolute path. Show Sample Output
This is sample output - yours may be different.
```
/tmp/foo/bar/baz/super/bon/bon/ahoy
```
11

readlink -f ../super/symlink_bon/ahoy

rbs · 2009-06-23 17:46:08 9
Migrate existing Ext3 filesystems to Ext4

Before doing this, back-up all data on any ext3 partitions that are to be converted to ext4. After running previous command you MUST run fsck, is needed to return the filesystem to a consistent state. fsck -pDf /dev/yourpartition Edit /etc/fstab and change the 'type' from ext3 to ext4 for any partitions that are converted to ext4.
This is sample output - yours may be different.
5

tune2fs -O extents,uninit_bg,dir_index /dev/yourpartition

starchox · 2009-06-23 17:42:01 14
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Rename files in batch

determine if tcp port is open

for udp nmap -sU -p 80 hostname

prevent large files from being cached in memory (backups!)

We all know... $ nice -n19 for low CPU priority. $ ionice -c3 for low I/O priority. nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop. http://askubuntu.com/questions/122857 https://github.com/Feh/nocache http://packages.debian.org/search?keywords=nocache http://packages.ubuntu.com/search?keywords=nocache To undo caching of a single file in hindsight, you can do $ cachedel To check the cache status of a file, do $ cachestats

distribution specific information

list all file extensions in a directory

Just a little simplification.

Create a backup of the file.

It will create a backup of the filename. The advantage is that if you list the folder the backups will be sorted by date. The command works on any unix in bash.

The Hidden PS

While going through the source code for the well known ps command, I read about some interesting things.. Namely, that there are a bunch of different fields that ps can try and enumerate for you. These are fields I was not able to find in the man pages, documentation, only in the source. Here is a longer function that goes through each of the formats recognized by the ps on your machine, executes it, and then prompts you whether you would like to add it or not. Adding it simply adds it to an array that is then printed when you ctrl-c or at the end of the function run. This lets you save your favorite ones and then see the command to put in your .bash_profile like mine at : http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Note that I had to do the exec method below in order to pause with read. t () { local r l a P f=/tmp/ps c='command ps wwo pid:6,user:8,vsize:8,comm:20' IFS=' '; trap 'exec 66

get diskusage of files modified during the last n days

get diskusage of files (in this case logfiles in /var/log) modified during the last n days: $ sudo find /var/log/ -mtime -n -type f | xargs du -ch n -> last modified n*24 hours ago Numeric arguments can be specified as +n for greater than n, -n for less than n, n for exactly n. => so 7*24 hours (about 7 days) is -7 $ sudo find /var/log/ -mtime -7 -type f | xargs du -ch | tail -n1

Write comments to your history.

A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Search for a string inside all files in the current directory

options: -n line nbrs, -i ignore case, -s no "doesn't exist", -I ignore binary args: * for all files of current dir (not hidden), .[!.]* for all hidden files I don't include by default the -R (recursive) option, which is not always useful. You add it by hand when needed.

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