Quote: (07-18-2013 11:33 PM)michelin Wrote:
Look at your smartphone. Android has a Linux kernel, his invention.
Hold on there, tiger.
Dennis Ritchie and Ken Thompson invented
Unix, and the
C language, while working for Bell Labs in 1969 on junky old out-of-date computers no one else in the office thought were useful anymore. Because of some anti-monopoly policies Bell Labs couldn't sell this operating system, so they gave it away free, and later sold licenses for under $1000, as a bonus for doing business with them. The source code for the OS was even printed out in its entirety and
published in book form in the 1970s. Unix spread through universities, particularly UC Berkeley, because it was free, and because it was very good at integrating the junky old computers that second and third tier projects would inherit.
Some time in the 1990s there was a "Hey, why aren't we getting money from this?" moment by Bell Labs sales guys, and they made an effort to get everyone using Unix to pay up money they obviously didn't have. So in 1991 the then 22 year old Linus Torvalds sat down and typed in by hand the Unix Kernel source that was already well known (it was written the year of his birth), using printed sources, but not using any of the electronic source tapes, and using a independently written C compiler, which at the time was good enough to establish it as legally not Bell Labs's software under the laws of his country of Finland. He then released this as an open-ware, royalty free alternative to Bell Lab's Unix that worked exactly like it, but Bell Labs couldn't charge for. Bell Labs gnashed their teeth, but the Finnish government backed him up --largely because it saved them money at their universities. The end result of this greed is no one talks about Unix anymore (which might lead to royalty payment requests) and everyone talks about Linux now (unquestionably royalty free).
Your cell phone may be running a flavor of linux, but it's been long modified beyond anything Linus Torvalds could understand.
WindRiver is the largest creator of embedded Operating Systems. Your cell phone most likely runs their handiwork, not anything Linus compiled.
The
kernel is simply the core of the Operating System that runs in a loop repeatedly, looking for work to do. You want to keep it as small and fast as possible, and actual patches to the kernel itself are rare because that could introduce a cross-platform bug. Instead, most all patches are to secondary parts of the operating system that interface with the kernel, like device drivers. This way bugs are encapsulated: when Sarah Sharp introduces a bug to Intel USB 3.0 support, she only fucks up her own customers, and they get to yell at her until she finds an engineer to fix it for her. If Sarah ever was allowed to submit a change to the actual kernel (not likely, since she can't even tell the difference between the two), it could introduce an all platform bug that would knock down everyone's system. That would leave a lot of people angry at Linus Torvalds, so it's something he's very unlikely to ever do.
