Datasheet

The Linux Kernel
The Linux kernel came along much later than the GNU project itself, over a decade after Richard
Stallman made his initial announcement. In that time, other alternate systems had been developed.
These included the HURD microkernel (which has since garnered limited general interest outside of the
enthusiastic core developer community), as well as the educational Minix microkernel that had been
written by Andrew Tanenbaum. For various reasons, neither of these alternative systems was widely
considered ready for prime time by general computer users when Linux first hit the scene.
Meanwhile, a young Finnish student, working at the University of Helsinki had become frustrated about
many of the things that he considered broken in the Minix operating system.
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Thus, he began work on
his own system, designed specifically for his (at the time cutting-edge) AT-386 microcomputer. That per-
son was Linus Torvalds, and he would go on to lead the project that has created a whole industry of
Linux companies and spurred on a new generation.
Linus sent out the following announcement to the comp.os.minic Usenet newsgroup upon the initial
release of Linux in the summer of 1991:
Date: 25Aug 91 20:57:08 GMT
Organization: University of Helsinki
Hello everybody out three using minix – I’m doing a (free) Operating system (just a hobby, won’t be big
and professional like gnu) for 386(486) AT clones. This has been brewing since April, and is starting to
get ready. I’d like any feedback on Things people like/dislike in minix, as my OS resembles it somewhat
(same physical layout of the file-system (due to practical reasons) among other things).
I’ve currently ported bash (1.08) and gcc(1.40), and things seem to work. This implies that I’ll get
something practical within a few months, and I’d like to know what features most people would want.
Any Suggestions are welcome, but I won’t promise I’ll implement them.
Despite Linus’s initial modesty, interest in the Linux kernel grew quickly around the world. It wasn’t
long before several release cycles had passed and a growing community of users—all of whom were
necessarily developers; simply installing Linux required a great deal of expertise—were working to
solve technical challenges and implement new ideas as they were first conceived. Many of the now infa-
mous Linux developers became involved early on. They enjoyed being able to work on a modern
entirely Free UNIX-like system that didn’t suffer from design complexities of alternative systems.
Linux developers relied upon the many existing GNU tools to build the Linux kernel and to develop
new features for it. Indeed, it wasn’t long before interest grew beyond the early developers, and Minix
users began to work on Linux instead — something that ultimately led to a series of well-known “flame
wars” between the creator of Minix (Andrew Tanenbaum) and Linus Torvalds. Tanenbaum maintains to
this day that the design of Linux is fundamentally inferior to that of Minix. Philosophically, this may be
true, but the same can be said of other modern operating systems.
You can learn more about the historical heritage of Linux and other UNIX-like operating systems in the
book A Quarter Century of UNIX by Peter H. Salus (Addison-Wesley, 1994).
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Chapter 1: Working with Linux
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Many of these issues remained for a number of years and would prove the topic of a large amount of
conversation on the early Minix and Linux newsgroups. In latter years, the rivalry has largely sub-
sided as Linux has asserted its dominance in the marketplace and Minix (and its various successors)
has continued to be of academic interest to those contemplating future Operating System design.
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