Planet TwinClinG

Balaji Narayanan: From devil to the deep sea

Sat, 04 Feb 2012 15:46:01 +0000

I have been using two mobile phones, one a Nokia E75 for my personal use with a BSNL Cellone connection and an Airtel Blackberry for office use. It had been a pain to carry two phones but I let it be for almost an year. Last month, my E75's display died. I figured out that it would cost about Rs.2500 to get this fixed but if I tried it sell it would fetch me much less. I decided to use this opportunity to port my existing number to Airtel and do away with the need for a second phone.

I thought this would be an easy job but little did I know it would take so much effort. According to the process, it is as simple as sending an SMS to 1900, get a UPC number and submit a form to the new provider and voila, the magic happens.

But Cellone ruins this magic. For one whole day, any SMS to 1900, would result in a reply from 1901 with invalid message format, please send message 'PORT ' to 1900. I read, re-read, tried and retried in vain. Infact another co-worker said, I was sending it wrong and tried the same thing and failed.

The next day, I requested Vasu to call customer care to see if they could help. Their customer care was a serious joke. I was surprised how I lived with this pathetic support for such a long time. Thankfully, I never had to call them.

The next day I decided that I would walk into their CSC to see if it would help but wanted to give 1900 a last try and thankfully it worked. I thought it was the end of all my woes and walked into a Airtel Relationship Center for MNC. The guys were very pleasant, even waved off the paltry Rs.19 fee for MNP and told me that it would be ported and activated within a week.

In a few days time, I got a message from Airtel that my number would be ported the next day. Next morning, I inserted the new SIM into the BB and it worked. I called customer care to enable the BB plans and I was back to business with in a couple of hours.

Now I thought it would be another call to Airtel Customer care to get my existing Airtel BB connection cancelled. I called the customer care and they tried to woo me to keep the connection by giving me a bunch of offers. With great difficulty, I coaxed the customer care executive to take the request and give me a request number. When she finally did provide a request number, she told that the request would be completed in a month? I was baffled and asked again to be sure? It takes a couple of hours to activate a new connection but a month to disconnect one. :) And since the next day, for almost a week, I was getting calls to see if they can provide a better deals, so that I can keep the connection active. I got frustrated and showered my choicest cuss words and got them to deactivate the number. Last week I got a bill from Airtel for the old number with excess rental being charged. I am still fighting with them to get this resolved. Despite that, I still get emails from them every week if I would be interested in reviving that connection.

From devil to the deep sea, the network follows...

Shakthi Kannan: 25th International Conference on VLSI Design

Sun, 15 Jan 2012 13:20:00 +0000

I attended the 25th International Conference on VLSI Design and 11th International Conference on Embedded Systems between January 7-11, 2012 at the Hyderabad International Convention Centre, Hyderabad, India. The first two days consisted of tutorial sessions, and the next three days had the conference presentations. There were also exhibit stalls from different companies.

On the first day I attended the tutorial session on SystemC AMS extensions by Markus Damm, Sumit Adhikari, and François Pecheux. Chitlesh Goorah had earlier tried to get SystemC into Fedora and Fedora Electronic Lab, but, due to licensing issues it could not be included. SystemC-AMS is now released under Apache license. Open SystemC Initiative and Accellera Unite have now integrated to become Accellera Systems Initiative. We hope to work with them to get their sources under a single free/open source software license. François Pecheux is from Laboratoire d'Informatique de Paris 6, Pierre & Marie Curie University (UPMC), Paris, France, and we already ship their free/open source EDA tools in Fedora.

On day two, I attended the tutorial session by Sridhar Arvind on 3D-ICE, a free/open source interlayer cooling emulator from Embedded System Laboratory, Ecole polytechnique fédérale de Lausanne, Switzerland. I have already been working with Sridhar, Prof. David Atienza and Alessandro Vincenzi on testing 3D-ICE on Fedora. I had built and tested the dependency SuperLU library and the 3D-ICE package before the tutorial session. Their software has already been downloaded by over 70 research labs around the world. I will push our tested changes to them. On the later half of the day, I attended a session on verification constraint complexity. Teal is a useful verification utility and connection library that has support for constraints and parameter control. The authors of the tool had agreed to release it as free/open source software, and we also ship it in Fedora.

On the following three days of the conference, I attended various paper presentations from different tracks from reconfigurable architectures to methods in AMS optimization. I met Prof. Susmita Sur-Kolay from the Indian Statistical Institute, Kolkata, India where they run Fedora in their labs. They also wished to use the 3D-ICE tool and GPU tools in their labs. I also visited the exhibit stalls meeting different people from the industry and academia. There are quite a few interesting free/open source tools that users can benefit from, and we will work in making them available in Fedora. In 2013, the conference will be held in Pune. Thanks to Red Hat for sponsoring my travel and participation at the conference.

Thejaswi Puthraya: Behind the Scenes: From request to response

Mon, 02 Jan 2012 20:45:23 +0000

Cross posted from my work blog.

In the previous installment of "Behind the Scenes", we saw how the control flows from Form to File Storage. Today, we are going to see how the application reacts from request to response.

In this post, we are going to assume that we are using django's inbuilt runserver. The flow doesn't change much for other WSGI servers available.

When you invoke the runserver management command, the command line options are validated and an instance of WSGIServer is created and passed the WSGIRequestHandler, which is used to create the request object (WSGIRequest). After the request object is created and the request started signal is fired, the response is fetched through the WSGIRequestHandler.get_response(request).

In the get_response method of the request handler, first the urlconf location (by default the urls.py) is setup based on the settings.ROOT_URLCONF. Then a RegexURLResolver compiles the regular expressions in the urlconf file. Next, the request middlewares are called in the order specified in the settings.MIDDLEWARE_CLASSES followed by the view middlewares after matching the view (callback) function against the compiled regular expressions from the urlconf. Then the view (callback) is invoked and verified that it does not return None before calling the response middlewares.

You can see the pictorial representation of the flow below:

Shakthi Kannan: Tux workshop, MindSpark 2011, CoEP, Pune, Maharashtra, India

Wed, 28 Dec 2011 12:05:00 +0000

I had conducted an introductory session on Fedora as part of the Tux workshop, MindSpark 2011 at College of Engineering, Pune, Maharashtra, India on Tuesday, December 27, 2011.

There were hundred participants distributed between the morning and repeat sessions in the afternoon. I explained about hardware architecture, system boot sequence, and discussed basic installation concepts to the participants. I then gave a demo of installing Fedora using Virtual Machine Manager. I showed them the plethora of F/OSS software that they can use, and also discussed about Fedora sub-projects, and basic project/communication guidelines. I have given them F16 ISO DVD images.

Thanks to Sanket Mehta for working with me for a month in organizing this workshop. Few photos taken at the event are available in my /gallery.

Thejaswi Puthraya: Sencha Touch vs jQuery Mobile

Thu, 15 Dec 2011 20:07:13 +0000

Generally, I don't like to do a comparison of technologies or products in a single post because each deserves a dedicated post. But such type of posts get obsolete fast and the effort put into writing (not researching) them goes waste.

Before I start off the comparison, I need to explain the workflow of developing mobile apps at work. Sai, the chief designer, draws the mockups on paper, then prototypes on Photoshop and sends them for the approval from the client. The client then suggests some changes and a final set of screens (PSDs set in order) are sent to the developers. We prefer to write HTML5 apps running on phonegap because it gives us the ability to create cross platform apps effortlessly (well almost) and we write once (and in stuff we are most comfortable with) and deploy everywhere (well again almost). Another note to make is that we specialize in writing web apps and are at home with jQuery. So take our comparison with a slight pinch of salt.

Now based on the background above, here is the brain dump of the comparison between Sencha Touch (v1.1) and jQueryMobile (v1.0)

Pros for Sencha

Everything is JS (JS generates the DOM for you)
Oldest mobile app framework.
MVC pattern (neat separation of models, views and controllers)

Cons for Sencha

Difficult to design layouts as it requires knowledge of JS. (Web) Designer unfriendly!
Negligible documentation (Needs a lot of love).
Too much dependence on global variables. Debugging mess.
Difficult to theme. Requires messing around with JS and SCSS.
Feels like using the bad parts of JS. Lots of new operator, globals and an awkward API.
Only supports webkit based browsers (hence suitable mainly for mobile apps)
The code repo is available to you on only if you purchase support and development is mainly done within Sencha company.

Pros for jQMobile

It's jQuery!
Active ecosystem. Lots of plugins.
Better documentation
Finer control of the HTML. Can use full power of HTML5.
Dead easy to make themes. Have an online ThemeRoller!
Supports majority of the browsers (http://jquerymobile.com/gbs/)
Can be used for mobile site as well as mobile app (embedded webkit)
Development is open and happens publicly with the support of the community.

Cons for jQMobile

Just reached 1.0. Fairly young but very promising.
No MVC. Lot of care has to be taken while organizing the code.

Shakthi Kannan: Travel: Wai and Mahabaleshwar, Maharashtra, India

Tue, 13 Dec 2011 09:40:00 +0000

I had been on a weekend trip to Wai and Mahabaleshwar, Maharashtra, India. More photos in my /gallery.

Shakthi Kannan: Fedora workshop at Foresight Institute, Pune

Sun, 04 Dec 2011 10:15:00 +0000

I had conducted a one-day introductory workshop on Fedora at Foresight Institute of Management and Research, affiliated to University of Pune, Maharashtra, India on Saturday, December 3, 2011.

I started the day's proceedings with an introduction to free/open source software. Most of the students who participated were studying towards their bachelor's programme in computer applications (BCA), and were familiar with C, C++ and Java development. I gave a demo of the Fedora desktop, and also showed them the plethora of software that they can use.

I also introduced them to revision control with examples on using git. I also addressed the various communication tools that we use, the basic communication guidelines, and the Fedora sub-projects that they can participate in.

During the post-lunch session, I explained to them about copyright, trademarks, and licensing, and how to use them. I explained the basic concepts in installation, and gave them a demo of installation of Fedora. I have given them CD/DVD images of both Fedora 15 and 16.

Thanks to Antriksh Shah for working with me for a month in organizing this workshop.

Balaji Narayanan: RIP Steve Jobs

Fri, 25 Nov 2011 07:39:32 +0000

I am not a mac fan boy. For that matter, I am not a gadget freak. I have been using a Mac for a couple of years. I very recently started using an iPod and an iPad, all thanks to Yahoo! And I am amazingly impressed by both the devices. I am sure both these devices are going to change the way I look at gadgets.

May be that is why, when I woke up this morning to the news of Steve Jobs death, I felt as if someone close to me has died. Even after all the fun we had today, somewhere in the bottom of my heart, that sorrow feeling lingers on.

RIP Steve Jobs. You have changed the way people will look at gadgets.

Srikrishna Das: Linux swapping even if RAM is available..

Thu, 24 Nov 2011 09:57:37 +0000

I noticed this after a very long time, on my laptop today…thought I’d just blog up what to do about it krish@shenron:~$ free total used free shared buffers cached Mem: 5717368 1556752 4160616 0 32116 295768 -/+ buffers/cache: 1228868 4488500 Swap: 4296696 156708 4139988 So, that’s pretty much more than 2/3 rds of RAM available, [...]

Shakthi Kannan: Shakthimaan's Tweets

Mon, 14 Nov 2011 06:10:00 +0000

Shakthimaan's tweets are now available for reference at http://www.shakthimaan.com/links/tweets.html. I use identi.ca and twitter for documentation links, book references, and useful tips. I am now making it available for others as well. You can also get the sources at:

  $ git clone git://gitorious.org/shakthimaan-tweets/mainline.git

Shakthi Kannan: Emacs ERC nick notification

Sun, 13 Nov 2011 02:40:00 +0000

I use the following code in .emacs with Emacs ERC to get notified using notify-send whenever anyone pings me on IRC:

(defun erc-global-notify (matched-type nick msg)
  (interactive)
  (when (eq matched-type 'current-nick)
    (shell-command
     (concat "notify-send -t 8000 -c \"im.received\" \""
             (car (split-string nick "!"))
             " mentioned your nick\" \""
             msg
             "\""))))
(add-hook 'erc-text-matched-hook 'erc-global-notify)

Shakthi Kannan: FUDCon Pune - Design Work

Sat, 12 Nov 2011 18:30:00 +0000

As part of the FUDCon Pune 2011 organizing team, I had volunteered to help with design work. After attending few training sessions on Inkscape by Máirín Duffy, I decided to give it a try. Ian Weller had written a Python script to create name badges with Inkscape. It would read list of names from a comma separated file (csv) file, and would generate pdfs from the design provided in the svg file. I had customized the script with help from Dave Malcolm, created csv files for speakers, volunteers and registered delegates, and generated over 400 named badges for the FUDCon event.

Thanks to Kushal Das for the photograph.
Badges printed on green paper would be for volunteers and organizers, while those printed on blue paper were for speakers. Everyone else got their names printed on white paper. We had also printed badges with just the FUDCon Pune logo for people who register at the venue to write their names on it. We decided not to use QR codes. If we had data on the delegates such as t-shirt size, food preference, identi.ca/twitter feed, IRC nick names, we could have printed them on the badge as well. I did leave enough white space, so people could write whatever they want. The scripts, the Inkscape svg design, an example csv and sample pdf generated are available at http://shakthimaan.fedorapeople.org/docs/fudcon. I had also designed the coupons for lunch, day I and II, and for the FUDPub:

Shakthi Kannan: FUDCon Pune - Final Day

Tue, 08 Nov 2011 03:45:00 +0000

As a follow-up to my talk on QUCS on day II of FUDCon Pune 2011, I wanted to create circuit examples on the final day from a text book that was being followed for basic electrical engineering course work. This would be a supplement that a student can use when learning circuit theory. Anuj More and Payas Awadhutkar joined in, and we worked on schematics from chapter I of 'Fundamentals of Electrical Engineering' by Leonard S. Boborow, a.k.a "Babu Rao" in India. The schematics were created in qucs-0.0.16, and are available from Payas Awadhutkar gitorious repo:

  $ git clone git://gitorious.org/qucs-baburao/qucs-baburao.git

As a finale to the event, Jared Smith cut the Fedora cake!

I would like to thank all the volunteers from College of Engineering, Pune and Prof. Abhijit A M who coordinated with us in organizing this conference. Thanks also goes to the Fedora contributors who helped in getting things done. Special thanks to Red Hat for sponsoring the event, and for their wonderful support. The COEP volunteers:

We trained many students over the years as part of the Fedora project. I was very happy to see them as speakers and present on the things that they have been working on, and also help others when required during the conference. This is the best outcome that I take from the event.

All the photos taken at FUDCon Pune 2011 are available in my /gallery.

Shakthi Kannan: FUDCon Pune - Day II

Mon, 07 Nov 2011 17:40:00 +0000

I arrived early again on day II of FUDCon Pune 2011. The day's proceedings started with a keynote by Harish Pillay on his thoughts on community work, and on his new role as the lead of Community Architecture. I then attended the 'Security in the Open Source world!' talk by Eugene Teo and Huzaifa Sidhpurwala. Their talk covered quite a bit on the various security threats, and on how they are handled.

Since I attended the GlusterFS overview talk on the first day, I wanted to follow it up with the 'GlusterFS: Hacking HOWTO' talk by Amar Tumballi. He suggested newbies to read on translators as a starting point to work with Gluster, along with few ideas that they could start with. Lunch was again served at 12 noon. After lunch, I headed to Seminar Hall 2 for my talk on 'Quite Universal Circuit Simulator - A Qt Love Story' (QUCS). It is an introduction to electrical circuit theory using circuit components as "fictional" men and women. The example circuits were created using qucs-0.0.15. The examples are available at the gitorious repo:

  $ git clone git://gitorious.org/qucs-a-qt-love-story/qucs-a-qt-love-story_prj.git

After my talk, I went to the auditorium to attend the talk by Amit Shah on 'Linux Virtualization' followed by Kashyap Chamarthy's talk on 'Virtualization with Libvirt'. They had given a good overview of virtualization in the Linux kernel, and available tools that one could use. I do use Publican, and thus attended Jared Smith's talk on the same. Publican does insert blank pages to ensure that new chapters start on the right-hand side if the content were to be printed as a book. For the final talk of the day, I attended Rahul Sundaram's session on Askbot for Fedora, and the roadmap and features that he is interested in. We then travelled to Hotel Parc Estique for the FUDPub!

Shakthi Kannan: FUDCon Pune - Day I

Mon, 07 Nov 2011 12:40:00 +0000

I arrived early on day I of FUDCon Pune 2011 to help with the registration desk. We had different counters for speakers and volunteers, and for delegates. A printer was available for us to print badges, directions, or posters as required.

I attended the keynote by Jared Smith, the Fedora Project Leader. The illustrations used in his presentation, 'Fedora "State of the Union" Address' were really good. I then proceeded to the classrooms to attend Ramakrishna Reddy's talk on 'Developer Survivor Manual'. He addressed essential things that newbie developers need to know, and demoed various revision control systems. Fedora banners were placed at various seminar locations on campus to indicate where the talks and sessions were being held.

Lunch was served at 12 noon, and then I moved on to attend the 'Fedora Remix and the Community' talk by Danishka Navin. He shared his experience with the Hanthana project, which is a Fedora remix that has support for Sinhalese, and Tamil and has been deployed at various schools in Sri Lanka. Fedora is one of the first and largest user of gitolite, and I was happy to meet its author, Sitaram Chamarthy, from TCS Innovation Labs, Hyderabad, India. His talk was filled with numerous examples from people using gitolite. The other large users of gitolite are KDE and kernel.org. I then attended the 'GlusterFS' talk by Krishna Srinivas from Red Hat, who gave an overview of the Gluster file system, its architecture, and uses.

Shakthi Kannan: Going to FUDCon Pune

Fri, 04 Nov 2011 00:05:00 +0000

I had filed a ticket year-end of 2009 to Fedora India to organize a FUDCon in India. We couldn't make it in 2010, but it is happening this year!

Balaji Narayanan: Locate Your Hacks

Fri, 14 Oct 2011 17:04:34 +0000

I am at IIT Delhi for the Hack U. It has been a fun event so far with some interesting discussions on hacks. Met with a bunch of students who are working on their PhD thesis and some of them were awesome. Let us see how the rest of the event goes.

My presentation from the event is on slideshare.

Locate Your Hacks

View more presentations from Balaji Narayanan

Shakthi Kannan: Fedora Activity Day II, Pune, 2011

Mon, 10 Oct 2011 07:45:00 +0000

In preparation to FUDCon, Pune 2011, we had organized our second Fedora Activity Day (FAD) at the FOSS Lab, College of Engineering, Pune, India on Saturday, October 8, 2011. Thanks to COEP for hosting the FAD, and to Prof. Abhijit for working with us in organizing the same. Saleem Ansari had setup http://fudcon.in using Conference Organization Distribution, which we used it for registration at the venue.

Prasad Pandit started the day's proceedings with an introduction to Python. Basic syntax, semantics of Python were covered, and we helped the participants in getting started in writing simple scripts. I then presented an overview of contributing to Fedora using the i-want-2-do-project. tell-me-wat-2-do-fedora presentation, and the various communication channels that they need to be familiar with to work with the larger Fedora community.

We had lunch at the COEP Boat Club canteen. After lunch, Kashyap Chamarthy presented KVM virtualization in Fedora illustrating examples using libvirt and virt tools. Amit Shah and Kashyap answered queries regarding virtualization. Saleem Ansari then presented an introduction to web development and Django, illustrating the use of model, view and template design. I concluded the day's sessions with an introduction to git using the di-git-ally managing love letters presentation.

Few photos taken at the event are available in my /gallery.

Shakthi Kannan: Shaastra 2011, IIT Madras

Mon, 03 Oct 2011 10:10:00 +0000

The Shaastra team has been trying to get me to speak at their event for many years. This year I wanted to make it, and as part of the Hackfest at Shaastra 2011, September 28 to October 2, 2011 at IIT-Madras, Chennai, India I had presented the talk on i-want-2-do-project. tell-me-wat-2-do.

Most of the students were interested in participating in the Google Summer of Code program. I was also able to meet and talk with past Google Summer of Code students, who had already been introduced to this presentation.

I visited the IITM Research Expo at the K V grounds on campus where students had presented their research work. There were quite a few interesting papers on MEMS. I also attended the Paper and Poster presentation by students at the IITM Research Park. A small memento that I received:

Sudharshan: Chile, allá vamos!

Sat, 01 Oct 2011 13:13:51 +0000

It all started as a little hack by Srini and I at the Yahoo! Openhack Event conducted in Bangalore. The hack by itself wasn’t that fancy when compared to the other finalists but we did feel good when our hack got shortlisted for the finals. We wrote a little web app which would index delicious [...]

Shakthi Kannan: Fedora Activity Day I, Pune, 2011

Sun, 25 Sep 2011 06:30:00 +0000

In preparation to FUDCon, Pune 2011, we had organized a Fedora Activity Day (FAD) I at Red Hat, Pune, India on Saturday, September 24, 2011.

Rahul Sundaram started the proceedings with a session on how to contribute to Fedora, and how people can get involved with the community. I showed the various communication channels that people need to use to connect with the large Fedora community.

We then proceeded to do a hands-on session on RPM packaging. We used the GNU Hello RPM packaging example from the fedoraproject.org wiki. Rahul and I explained each section of the .spec file, and showed them how to use rpmbuild. The participants learnt to write the .spec file, and also built, installed, and tested the hello package.

We then took a break for lunch following which I presented a hands-on session on git using the di-git-ally managing love letters presentation. Siddhesh Poyarekar then took an introductory hands-on session on autotools.

All the presentations are available in the FAD wiki page. Thanks to Red Hat for letting us use their facility, and for sponsoring the pizza! They were able to arrange for ten laptops with Fedora 15 installed for participants who didn't have laptops.

Thanks also to Kashyap Chamarthy, Kushal Das, Siddhesh Poyarekar for their help to the participants during the workshop sessions.

Balaji Narayanan: Decathlon

Sun, 25 Sep 2011 04:19:43 +0000

In June, while I was preparing for my trek to Roopkund, I was looking for trekking shoes. I was recommended Forclaz 500 Ventiv by friends. The shoe was retailing at Rs.2999 at Decathlon. The same was available for Rs.2499 online with free shipping. I went to the store to try it out, thinking that will order online and save Rs.500. John, the salesman helped me out with my questions and suggested that I pick up a tight fit. It was too tight but he suggested that it will expand a bit and will be fine. He also promised that he will replace it if I find it uncomfortable after a couple of days use. I told him about the online store and price and he told me that he can give it to me for 2799 and joked that Decathlon needs to pay him salary and hence cannot match that price. I bought the shoe and paid the premium just for his service.

A couple of days burn-in did not help and it was causing pain in the toe. I called up the store and Kuldeep another salesman at the trekking section suggested that I bring in the shoe for replacement. I picked up one size bigger and it was very comfortable for most part of the trek.

On the last day of the trek, thanks to heavy snow and rain, the shoe lost its shape. There was a bulge around the ankle support and due to this the show wasn't stable, causing ankle strain. After I reached Bangalore, I called up the store and mentioned about the problem. Kuldeep asked me to bring the shoe along with the bill for exchange. I never had the time and I almost forgot about it. Last week I remembered and took the shoe to the store. I had already lost hopes but wanted to give it a shot.

I walked into the store on Sunday, explained him the problem and showed the shoe. Kuldeep / Jon, said only one thing "Give it at the counter calling it a defective piece and pick up a new one'. Absolutely no questions, no nagging, not trying to put the blame on the buyer, no delay.

This is an excellent example of customer service. I had to go to the store 3 times but I will never mind the distance of driving 20+ KM to the store for such excellent service. Looking forward to the store opening in Bannerghatta Road. I am a Decathlon convert.

Thejaswi Puthraya: Behind the Scenes: From HTML Form to Storage

Wed, 21 Sep 2011 18:01:51 +0000

Cross posted from my work blog post

In this post, we are going to see what happens behind the scenes when a file is uploaded to a django powered web application.

An HTML form with a file input (atleast one) and encoding set to multipart/form-data is submitted. The MultiPartParser parses the POST request and returns a tuple of the POST and FILES data (request.POST, request.FILES). The MultiPartParser processes the uploaded data using the File Upload Handlers objects (through the new_file, receive_data_chunk and upload_complete methods). The request.FILES values are a sequence of instances of UploadedFile.

In the django form, we pass the request.FILES MultiValueDict. These UploadedFile instances are validated by the full_clean method on the Form. The full_clean method in turn calls the _clean_fields method which calls the clean method on the forms.FileField and checks if the data is empty.

After the form is successfully validated, we might assign and save the cleaned_data of the form to a model instance (or by saving the ModelForm). When the save method on the model instance is called, the save_base method calls a pre_save method on each field of the model. This pre_save method returns the value of the file instance bound to that FileField and calls it's save method. This save method (on the models.FileField) in turn calls the save (Storage) method on the Storage which is either picked up from the arguments passed to the FileField (FileField(storage=...)) or the DEFAULT_FILE_STORAGE settings attribute.

This is the flow from the HTML Form all the way upto the File Storage. Hope you liked it.

Shakthi Kannan: From Python to Silicon: python-myhdl

Tue, 20 Sep 2011 04:10:00 +0000

I had presented From Python to Silicon: python-myhdl talk at PyCon India 2011, September 16-18, 2011 at Symbiosis, Pune, India.

The first day of the (un)conference was filled with tutorials. I attended the Functional Programming with Python talk by Anand Chitipothu. He had illustrated list comprehensions, recursions, higher-order functions, iterators and generators in Python with numerous examples.

On the second day, I attended the keynote by Raymond Hettinger on What Makes Python Awesome. It was a very informative talk illustrating the key characteristics of Python, and the community that surrounds it.

I also attended the Python on Android talk by Sajjad Anwar, who gave simple examples using android-scripting. The Emacs as a Python IDE talk by Noufal Ibrahim had useful tips and tricks on using Emacs for development work, and issue tracking using org-mode. I also attended the Decorators as Composable Abstractions by Sidhant Godiwala which was an introduction to using decorators in Python.

On the final day of the event, I attended Network Programming with Umit Project by Narendran Thangaranjan who gave demos on network protocol implementation, and testing in Python using the Umit project. Jivitesh Singh Dhaliwal gave a demo of using PySerial to control robots in the Python in the Real World: From Blinking LEDs to Advanced Robotics talk.

My presentation slides are available. Thanks to Christopher Felton for his valuable feedback.

Few photos taken during the event are available at my /gallery.

Thejaswi Puthraya: Installing drivers for Samsung ML-1676 on Linux

Sat, 10 Sep 2011 22:16:08 +0000

Today, I purchased a Samsung ML-1676 Monochrome Laser Printer. I was under the impression that most printers are now supported out of the box but I was wrong. This model of the printer uses a proprietary language called the Samsung Printing Language (SPL) and hence drivers are not included in the distributions by default. But fear not, there is a very simple process to setup your printer because Samsung provides drivers not just for Windows but also for Mac and Linux based distributions! Great going Samsung, you deserve a pat on the back.

Download the "Unified Drivers" for Linux from the download center on Samsung website. At the moment of writing this post, the drivers are available here.

Switch on your printer and connect it to your PC. Then, extract the downloaded file and start your printer configuration suite. On KDE, it is found under System Settings > Printer Configuration. Click on the "New Printer" option and select a "New Network Printer". Most likely, you will see a "Samsung ML-1670 Series" connection in the various printer connection options. If you do not find it, check if the printer is connected and switched on. Select the "Samsung ML-1670 Series" connection and proceed. In the next screen, select the "Provide the PPD file" (PPD - PostScript Printer Description) option and select the following file from your downloaded directory (<Download_directory>/cdroot/Linux/noarch/at_opt/share/ppd/ML-1670spl.ppd).

The driver for the printer is installed. All you now need is the 'rastertosamsungsplc' utility which translates the default print language to the Samsung Printer Language. This utility is also present in the download. Copy the 'rastertosamsungsplc' from the <Download_directory>/cdroot/Linux/<arch>/at_root/usr/lib/cups/filter/ directory to /usr/lib/cups/filter/ on your PC. Fill the <arch> in the path appropriately. If you use a 32-bit machine, arch would be i386 and x86_64 on a 64-bit.

Setting up this printer is a little bit of a struggle but once setup, it works perfectly.

PS: The option of providing PPD works for a lot of Samsung models and you may be lucky to find your model in the "Unified Driver" download.

Shakthi Kannan: Packaging RPM

Sat, 10 Sep 2011 03:40:00 +0000

Released Packaging RPM (Packaging Red hot, Paneer (butter) Masala) presentation 1.7. The LaTeX sources are available at gitorious.org.

  $ git clone git://gitorious.org/packaging-red-hot-paneer-butter-masala/mainline.git

Kenneth Gonsalves: fedora 15 sucks

Tue, 06 Sep 2011 11:02:39 +0000

I have been using fedora 15 for the last few months, but am unable to get my BSNL 3G to work. Why can't these clowns at redhat get their act together? My daughter had no problem with Fedora 14.

Shakthi Kannan: Introduction to GNU Make

Mon, 29 Aug 2011 08:40:00 +0000

I had presented GNU Make, Dum Ka Biryani, Make for each other at ICE-FOSS 2011, August 26-27, 2011 at Federal Institute of Science and Technology, Angamaly, Kerala.

The conference had talks, hands-on workshops, and project demos. There were interesting projects displayed at the stalls by the students varying from Arduino-based hardware projects, to Python mobile application development to games, and applications developed using opencv. Pamphlets were made for each project, and given to the visitors at the stall. I reviewed the projects that were demoed and gave them feedback. The Institute is in the process of migrating their servers, so we should (hopefully) see the sources made available online.

I also had a chance to meet Anvar K Sadath, Executive Director at the IT@School project. They have trained nearly 2 lakh teachers on F/OSS over the years. Their new initiative is animation training using free/open source software.

The Institute does have a cluster setup called "Dakshina" which is used by students, and the faculty. They also do allow other nearby colleges to use the facility on request.

Thanks to the Management of FISAT, for sponsoring my travel and for the wonderful hospitality. Photos taken during the trip are available at my /gallery.

Kenneth Gonsalves: irctc madness

Sat, 27 Aug 2011 02:47:05 +0000

circa 2000 I registered an account with irctc. Since I did not have a credit card, I did not use the account for a long time and forgot about it. Several years later when I got a card, I registered afresh and was using the account regularly. The other day the account got deactivated. I tried to register afresh - error, email id already registered. I tried with a different email id - error, mobile number already registered. I mailed customer care and they told me that by creating 2 accounts with the same email id/mobile number, I am in breach of the terms and conditions of the website and hence am banned - I am now waiting for the railway police to turn up with handcuffs.

Shakthi Kannan: Introduction to TDD, BDD: Pune Institute of Computer Technology

Mon, 22 Aug 2011 05:20:00 +0000

I had conducted a session on test driven, behaviour driven development on Saturday, August 20, 2011 at Pune Institute of Computer Technology, Pune, Maharashtra, India using Ruby, Cucumber, and Rails with examples from Diaspora.

Thanks to Praveen Arimbrathodiyil for initiating this workshop and Shreyank Gupta for helping the students during the hands-on session.

Participants were new to Ruby, and we started off with Ruby in Twenty Minutes. Using interactive ruby (irb) students were able to understand the language syntax and its usage. We then moved on to writing tests in Ruby, and writing them first before writing code.

User stories were introduced with explanation on understanding how features, and step definitions are written. Cucumber was used to run through the features with simple examples. We then moved on to using cucumber with Rails illustrating an example of a Rails blog application. I had setup Diaspora on my laptop, and had then given them a visual demo of how cucumber runs feature tests with selenium webdriver. Photos taken from Shreyank's camera are available.