How many lines of code does it take to create the Android OS | Hacker News Reader

How many lines of code does it take to create the Android OS

gubatron.com

16 pointsmun41114 comments

Wait, what? 3 million lines of XML. Oh yuck yuck yuck.

Beyond that, I'm surprised there's more C than Java, and doubly surprised that C++ comes in behind all of the aforementioned languages.

Much of the XML may be generated stuff? Does this include the kernel, which would be C?

According to Wikipedia the full linux 2.6 kernel tree is now around 12 million LOC. So I'd be guessing a good chunk of the 2.8 million lines of C in Android is the kernel. It'd really depend on how many lines the "core" parts of the kernel take up (not that much, I bet) but also how much is left in the Android tree even if it's not really used or even compiled in.

I'm also interested to know what makes up all that XML, though.

You're right. XML is about 25% of the code (~3M of ~12M lines, ignoring blank lines). And overall, some 20% of the project is comments (~3M comments of ~15M lines code + comment, again ignoring blank lines). And in spite of that, they appear to have several small things with no comments whatsoever. Most of the other stuff is about what you'd expect, though: the header files and assembly have the most comments, while the one-off programs have very few.

Still, I wonder what they used Lisp for? Or why they used so many different tools? I mean, Perl was all but made to replace awk & sed. Did they have several people who did little one-off tasks in their favorite language when they were pressed for time?

Must be nice to get the tools you want, though, instead of being subject to absurd decisions by superiors (think "Daily WTF material").

The Android robot to McCarthy: You get 144 lines to write in lisp. What would you like to write?

McCarthy to the Android robot: Umm. Curse out the other languages for being cheap knockoffs.

This looks like cumulative lines of code for all the projects that go into Android (across all the platforms that they are supported on.)

For instance C#, DOS Batch, IDL etc are listed. I don't believe that Android has a runtime for any of these.

FWIW, I'd be really interested to see this reorganised as LOC per component.

A project made up of 12 million lines of code, and Google can give it away for free. Mind boggling. There's not many can do that.

Well, Google can receive a huge chunk of that for free, add their contribution, and give that result away. It's still a great thing, but let's not forget credit for the shoulders they are standing on.

I'd be interested to know the numbers for the parts that are unique to Android, as well as how much has been added to parts that are not unique...

This really puts FONC in perspective.

PHP is making a disappointing showing with a whopping 3 LOC!

i think it should be a phpinfo() <?php phpinfo(); ?>

D?! Which D are we talking about here?

The one that comes after C.

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