Being the Free Software advocate that I am, I want to use as much Free Software as I can (and spread the world).

Disclaimer: no, I don't like to call what I use "Open Source". I prefer the things the RMS way and if you don't like the fact that I like his way, I'm afraid that you may miss some of the things that I have here, even if you don't necessarily agree with me.

In particular, I would like to use, see etc., the material that is available on the Internet, that people has put available for others to see. In particular, many Universities around the world are making the shift of being only in the classroom to being present in their students' lifes all the time. This is accomplished by putting their educational material available on-line.

A decade or two ago, this was usually accomplished by publishing the so-called "lecture notes" on the website of the course and maintaining mailing-lists with the currently enrolled students. The lecture notes were usually taken using the "Scribe method", where, for each class, one student is responsible of taking notes of the material, writing it in a "finished" form and distributing it back for all the other students. This was made in a round-robin fashion, as a means to spread the responsibilities among the students taking the course. Also, the most common tool used to edit the material, especially in Mathematically-oriented courses, was to typeset everything in LaTeX (or even plain TeX, in some cases).

The lecturer frequently distributed a template, which the students used and, this way, all the notes written by the students had the same, uniform look and style. The work was usually revised by the lecturer and, many times, it resulted in a kind of a book, published in DVI or PostScript form (latter, it became common to use PDF, as it is a format more popular).

Actually, it is still quite frequent (and welcome!) to produce such lecture notes. But, now, things have changed slightly. (I could discuss why things have changed the way they have, but it is beyond the scope of these short notes here.) People have been recording lectures in audio and, after the technology became more accessible, in video. Now, a new term is used for distributing those contents: podcasting. Essentially, a podcast is a way of publishing, say, audio so that people can subscribe to your "podcast" (sometimes also said to be a "channel"). It is very much like a radio program, where people tune in to listen to a given program.

The way most people use to distribute the "episodes" of such programs/podcasts is actually a combination of technologies, but nothing exactly new: the description of what is available is given in a format called RSS (which is a specialization of XML, but this isn't important for our subject matter) and the content is usually in form of MP3 files (or some variation of that).

OK, enough background. Now, there are on-line stores on the Internet that make available podcasts. Those podcasts are usually free of charge for the listener. Some of the most prominent stores nowadays are Apple's "iTunes Store" and Amazon's store.

Apple has created its "iTunes Store" to foster the use of its iTunes program and to boost the sales of its iPod digital players (and, also, to make some extra money). But people in the education field have seen that using a podcast would be a good way of sharing knowledge and Apple wouldn't loose this market: they invented the iTunes U, which is a way for Universities around the world to publish their content on "iTunes Store".

Several big Universities have been putting their content on Apple's iTunes-U. And, to see the directory of podcasts on iTunes-U, you have (in theory) to use Apple's proprietary program iTunes, only available for proprietary platforms: for Microsoft's Windows and for Apple's own Mac OS X. No Free Software alternative is officially supported, despite the fact that the blurb on the Universities pages say that only the access to the content has to be via iTunes and that the content can be used with any MP3 player or with programs other than iTunes. Yes, this means that the content is playable under Linux and Linux plays a big role in higher education environments.

So, isn't there a way to access the blogs avoiding the use of proprietary software? What about people that only want to use Free Software solutions or, not even a matter of desiring to use Free Software, having only access to Free Software?

Well, there is. Apple has changed the way that people use to get the contents from its iTunes store during time, but, now, it seems to be quite easy to grab it under a 100% Free environment. I have used this recipe for two Universities only so far, but it has worked perfectly well. The Universities in question are MIT and Stanford University.

Let's say that you come across a link with the format:

itms://deimos3.apple.com/WebObjects/Core.woa/Browse/mit.edu.1330383747.01330383754.1330693646

Such a link is usually not recognized by browsers without the help of extra software. In platforms where iTunes is available, the browser sends it to iTunes and iTunes takes the duty of connecting to the "iTunes Music Store" (that's where the "itms" thing at the beginning of the URL comes from, by the way). Pay close attention to the part mit.edu.1330383747.01330383754.1330693646. That is the important part of the URL here.

But it is quite easy to convert the link above to something that can be grabbed with a usual browser or, say, a program like wget or curl. Just write the link as:

http://deimos3.apple.com/WebObjects/Core.woa/DownloadTracksFile/mit.edu.1330383747.01330383754.1330693646.mp4

The part up to and including DownloadTracksFile/ is constant. Only the part after it is changed and taken from the original link.

There is another way of rewriting the link. Its format is:

http://deimos3.apple.com/WebObjects/Core.woa/FeedEnclosure/mit.edu.1330383747.01330383754.1330693646/enclosure.mp4

Notice that the middle part of this URL is the actual part that we alluded to. The rest is simply a constant thing.

Well, this way, we can get the contents of podcasts with Free Software in an automated way. That is, until Apple changes its scheme of doing things. But, by that time, we will already have the things we want and newer solutions can be devised soon.

So, let's fire those wget's and start to study things (or prozilla's, aria2c's etc, for some speed boost).

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