Tips4Linux.com

Remove DRM from Amazon Kindle’s ebooks using Linux

T4L — Fri, 20 Aug 2010 07:18:38 +0000

When you buy an ebook using your Kindle, there’s a 99% chance it’s a DRM file. That means you won’t be able to read it anywhere else but on your Kindle. And we won’t accept that. To be able to convert that file and remove its DRM protection, you need a set of Python scripts called MobiDeDRM.
Now open your Kindle and type 411 on the keypad. This will bring up a window containing information. Write down the 16-character alphanumeric Serial.
Through your computer, buy a book from Amazon.com and save it to your harddrive. The filename shoud be something like Book-Title.azw.
Be sure you have Python installed in Linux. In Ubuntu you can easily install it with sudo apt-get install python.
Extract de files from the MobiDeDRM.zip file and run one of them like this:

python kindlepid.py XXXXXXXXXXX

where XXXXXXXXXXXX is your 16-character Serial. The Terminal window will return something like

Mobipocked PID for Kindle serial# XXXXXXXXXXXXXXXX is Z1QFCDQ*74

That “Z1QFCDQ*74” string is what you need.
Now all you have to do to remove the DRM from the .AZW file is:

python mobidedrm.py Book-Title.azw Book-Title.mobi Z1QFCDQ*74

In a minute or so you should have a DRM-free MobiPocket book you can later convert in any other format you like. If that doesn’t work, try

python mobidedrm2.py Book-Title.azw Book-Title.mobi Z1QFCDQ*74

Convert eBooks in Linux

T4L — Tue, 17 Aug 2010 13:32:34 +0000

Say you just bought an Amazon Kindle or a Barnes and Noble Nook. You want to convert your eBook collection to .EPUB or .MOBI format. For this, install Calibre. The application not only provides you with a graphical way to manage your eBook collection, but also comes with a set of useful command-line tools. One of these is ebook-convert.
This tool can help you convert between tens of standard formats like EPUB, FB2, LIT, LRF, MOBI, OEB, PDB, PDF, PML, RB, RTF, TCR, TXT, HTML and more. Even CBR and CBZ (comic book formats) are supported.
The syntax is simple:

ebook-convert input_format output_format

For example, if you want to convert a comic book archive to something readable on an e-ink screen, use

ebook-convert filename.cbz filename.epub

ebook-convert filename.cbz filename.pdf

Not only will ebook-convert convert the file, but it will also trim the white spaces around the page so they will better fit the small screen of an electronic eBook reader.

Batch resize images using the command line in Linux

T4L — Tue, 20 Jul 2010 14:15:32 +0000

If you have a ton of images that need resizing, you can do it all with the imagemagick package:

cd /home/user/images
mkdir resized_images
cp /home/user/images/* /home/user/images/resized_images

Now that you have a copy of the files in resized_images, time to resize them all:

mogrify -resize 800 *.jpg

This will resize them all to a width of 800px while keeping the aspect ratio. If you want a fixed image size, you can specify it like this:

mogrify -resize 800×600! *.jpg

Find out active IPs in a Linux LAN

T4L — Fri, 04 Jun 2010 19:19:54 +0000

If you are on a LAN and wish to find out which computers in it currently have access to that certain LAN, you can use the following command:

for ip in $(seq 1 254); do ping -c 1 192.168.1.$ip>/dev/null; [ $? -eq 0 ] && echo “192.168.1.$ip UP” || : ; done

This will ping each computer on the 192.168.1.x subnet one time, with a one second interval between pings. The output should be something like

192.168.1.1 UP
192.168.1.17 UP
192.168.1.24 UP
…

UPDATE:

Alternatively, you can use netdiscover:

sudo apt-get install netdiscover
netdiscover -r 192.168.1.0/24

This will scan all the computers in that particular address range and present the active ones in a table that also provides a MAC address and a MAC Vendor line. Thanks go out to angelblade for this information.

USB devices not mounting in Lucid? Here’s a fix.

T4L — Sat, 15 May 2010 10:19:55 +0000

If you are pestered by the bug that doesn;t let you mount USB devices in Ubuntu Lucid Lynx, the issue is caused by the floppy module. Disable it with

sudo modprobe -r floppy

and reboot.

Fix Linux Kernel 2.6.32 and VMWare Workstation 7 issue

T4L — Tue, 11 May 2010 17:36:27 +0000

After you upgraded to Ubuntu Lucid, you might have noticed that VMWare has stopped working and can’t compile one of it’s modules. The solution to this is simple: download this patch and this script in the same directory. Make the script executable with

chmod +x patch-modules.sh

and run it with

./patch-modules.sh

Answer with “Y” to the questions and let it do it’s job. After it finishes, VMWare should be working just fine.

Install older .RUN and .BIN archives in Linux

T4L — Fri, 07 May 2010 16:45:54 +0000

When running older .RUN and .BIN archives in Linux, you might get the following (or a similar) error:

Verifying archive integrity…tail: cannot open `+6′ for reading: No such file or directory
Error in check sums 1237260170 2341625838

The solution is to make the installer believe it’s being run on an older version of GNU/Linux. Open a Terminal and paste this:

export _POSIX2_VERSION=199209

Install the archive, then delete the above ENV variable:

unset _POSIX2_VERSION

Is Linux better than Windows web hosting?

T4L — Wed, 28 Apr 2010 17:13:38 +0000

People often get confused on which OS is better on getting the best performance or what’s best suited for a website. And this question is often debatable since it usually depends on what programs or scripting language you are planning to run on your website. But we still can’t deny the fact that Linux is the more popular choice of many on the web. Why wouldn’t it be? It’s cheaper but still reliable and runs great. Plus, if you’re using scripts such as PHP, MySQL or Perl, then Linux hosting is usually the best way to go in terms of reliability and cost-effectiveness. Though, if you’re planning to use ASP, most people would opt for windows hosting. Also, both Linux and Windows offer FTP access but usually only Linux offer ssh or telnet access.

Those are only a few factors to weigh on when deciding which ones better for your own website. And sometimes, it’s just a matter of what you prefer to use since you still have to decide on which web hosting provider to go with. Even if you have the perfect OS, if your web hosting provider is not reliable enough, then your website can still end up with a lot of issues. That’s why choosing the right web host for your site is important.

Doteasy is one of the best domain name registrar since 2000 that also offers web hosting services. If you’re looking for a free hosting, then you really have to check what Doteasy offers with their free web hosting plan. You not only get great reliability but also better features such as host multiple domains and up to 10 email accounts. Now, that’s really hard to find on other free hosting packages. Aside from that, you also get free web site builders such as for setting up blogs, forums, photo gallery and more with their easy to use web tools and applications. They guarantee 99.9% uptime and no banner ads on your site like what you get with other web hosts. But, in case you needed more hosting resources, you can simply upgrade to their other affordable hosting packages. Whatever type of website you are planning to create, they always have a great hosting package that would suit that. With their current promo of any .COM/.NET/.ORG domain registration for only $7.95 a year, you can get a personalized domain name and enjoy Doteasy’s free web hosting service with coupon code 1003BPM.

Reposition the Ubuntu Lucid Lynx Light theme buttons

T4L — Tue, 27 Apr 2010 17:18:17 +0000

By default, the new Light theme that comes with the latest version of Ubuntu Lucid Lynx are positioned on the left. If you want to reposition them to the old-fashioned right side, hit Alt+F2 and type gconf-editor.
Click Apps > Metacity > General on the left sidebar and change the property of button_layout from

close,minimize,maximize:

:close,minimize,maximize

Find out details about your system’s temperature

T4L — Wed, 14 Apr 2010 10:47:53 +0000

To find out more about your system’s temperature, install acpi. Then do a simple

acpi -V

to get a listing similar to this one:

Battery 0: Full, 100%
Battery 0: design capacity 7800 mAh, last full capacity 4988 mAh = 63%
Adapter 0: on-line
Thermal 0: ok, 63.5 degrees C
Thermal 0: trip point 0 switches to mode critical at temperature 126.0 degrees C
Cooling 0: Processor 0 of 10
Cooling 1: Processor 0 of 10