How to solve "Package gtk+-3.0 was not found" & "fatal error: gtk/gtk.h: No such file or directory" errors in Linux

As of now some of the Linux distros don't come up with the gtk-3.0 libraries and development files by default.   Though Gnome application developers are asked to migrate to gtk3, most of the desktop applications are still in gtk2.  Due to these reasons gtk3 development files are not pre bundled with distros.  So, we have to install gtk3 development files, libraries manually to compile a gtk+-3.0 based GUI applications.

If your gtk3 program compilation ($gcc -o executable_name  program_name  `pkg-config --cflags --libs gtk+-3.0`) throws error something like this

Package gtk+-3.0 was not found
            (or)
fatal error: gtk/gtk.h: No such file or directory

which means your machine is not installed with the gtk3 development files.  
To install the package in debian based machines 

$sudo apt-get install libgtk-3-dev

To install in rpm based machines

$yum install gtk3-devel

After the successful installation your machine should return output something like following while you execute the command 
"sudo pkg-config --cflags --libs gtk+-3.0"

"-pthread -I/usr/include/gtk-3.0 -I/usr/include/pango-1.0 -I/usr/include/gio-unix-2.0/ -I/usr/include/atk-1.0 -I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/freetype2 -I/usr/include/glib-2.0 -I/usr/lib/i386-linux-gnu/glib-2.0/include -I/usr/include/pixman-1 -I/usr/include/libpng12  -lgtk-3 -lgdk-3 -latk-1.0 -lgio-2.0 -lpangocairo-1.0 -lgdk_pixbuf-2.0 -lcairo-gobject -lpango-1.0 -lcairo -lgobject-2.0 -lglib-2.0 
"
Now, you can compile your gtk3 programs happily... :)

How to view all feeds/articles (both read & unread) + How to change read status of a feed in feedly

How to view all feeds/articles (both read & unread) feedly

Since the closing announcement of google reader service from google, I have been engaged with feedly as my feed reader.  Though there are many other rss/atom feed readers available in the web & in the app store, I do like feedly a lot.  The main reason why I am using feedly as my rss aggregator is

1. I can import all my google reader subscriptions into feedly via OPML file seamlessly. (Ofcourse you must have downloaded the OPML file before the closing ceremony of google reader.)
2. feedly's simple yet intuitive design
3. Can be linked with your gmail account.
4. Can be configured in many devices & can sync
5. Can export the subscriptions into OPML file.


So, When I configured my feedly account  & added new subscriptions It shows only a few latest feeds of a website as unread and all others as read.  By default feedly shows only the unread article.  So, If I want How I can see all the feeds from a particular subscription?  There are 2 ways.

In Broser/web based login, Once you logged in you can see all your subscriptions. 

1. When you click on a particular subscription in the right top of your screen you can see a gear wheel/ tooth wheel kind of symbol.  Click on that and uncheck the option "unread only" under the category named filters.

2. In the Left bottom of you feedly home page one can find a link to "preferences".  Click on that and go to "Hide read posts" and select option "No".


If you have further queries refer feedly's FAQ page & feedly's Knowledge base.

How to change read status of a feed in feedly
feedly has lot of shrotcuts to manage the feeds and subscriptions. If you want to know about all the shortcuts, Once you logged in into your feedly reader in web browser press "?" which lists all the available shortcuts..

If you want to change the read/unread status of an feed/article click on that article and press "m" which toggles the status.

To go to next feed/article press "n" or "j"

To go to previous feed/article press "p" or "k"

How to download your online data from google, twitter, facebook?

   We people are living in the age of information both ours own and the public data.  We people are completely dependent on internet and the services provided by the giants like google, yahoo, facebook, dropbox, twitter, flickr so and so...

  Privacy of people and their online data becomes talk of the world(! town..), many online service providers(especially social networking media) give provision to their users to download their data.  We will see how to download data from google, facebook & twitter.

1.  Google



  By google's takeout , one can download his online data of google services like drive, g+, blogger, contacts, youtube etc (Ref the image about complete services).

  Once you go to the google's takeout homepage you are prompted to enter your username and password(yes! your gmail account).  After login you will see a webpage like the one in right side, either you can select all the services or few particular services.

Note:  Sadly google not provides the google reader data :(






2.   Facebook

• Login into your facebook account (or click here to go to settings directly.)
• Click on the wrench symbol(on right top) and select account settings.
• 
  
• Select General tab, click on the Downlaod a copy of your Facebook data link.
• Click on the Start my archive button.

3.  Twitter

• Login into your twitter account (or click here to go settings directly).
• goto settings (click wrench symbol on right top & select settings) 
• scroll down & click on Request your archive  

  Once the archive is ready, download link will be sent to your email registered with twitter.
   

How to install chrome extensions/plugins/add-ons from unofficial sites?

By default google-chrome browser allows to install the extensions that are got from google's chrome webstore only.  So, what if you not find a useful extension in chrome's web store but available/downloadable with some third party website...?   How to install those extensions(.crx files)?

* Basically the google-chrome's extensions are .crx files.
* The extensions that available with chrome webstore be installed directly
* To install these third party extensions do the following.

1. Open your chrome browser -> Click on the  symbol(at the right top, just below the close,minimize buttons of the browser window) -> Tools -> "Extensions"
2. Now open the directory where you have your third party chrome extensions(.crx files), then drag and drop the .crx file into the chrome browser tab where the "Extensions" is open.
3. Now google-chrome browser will prompt you with "cancel" & "add" button.  Click on the "add" button the extension will be added to the browser.

How to know your gmail friend is chatting(keyboard not video) from his android mobile or from browser?

Nowadays Smartphone user base is increased in multi-fold manner.  So while we chatting we don't know whether the person at the other end is chatting with you is using his browser and keyboard are he is chatting from his android mobile.

Picture 1. - Gmail gear

Here is the simple solution,
You just need to enable the google labs' Green Robot! 
So, how to do that
1. Login to you gmail account

2. Click on settings
    Your gmail setting is at the right top of the gmail window with the gear symbol(see picture1 gmail settings).  Click on that now you will get a drop down menu with options like settings, themes, help etc.  Select settings

3. Now gmail will load the settings page with options like General, Chat, Filters, Labs, Mail Forwarding etc(see picture 2 - gmail settings options).

Picture 2 - Gmail settings options

4.  Select labs and search for Green Robot! then enable it.  Thats all... :) !


Now in your chat window you can see a small Green/Red/Orange(according to active/idle/busy) Robot icon to some of your friends who are online but from their mobile.