Linus Torvalds, a Finnish university student, was using Minix, a simple Unix clone written by Vrije Universiteit (Amsterdam) lecturer Andrew Tanenbaum, but Torvalds was frustrated by its lack of features and the fact that it did not make full use of the (still relatively new) Intel 80386 processor, and in particular its “protected mode,” which allows for much better separation between the kernel and userspace. Relatively quickly, he got a working shell, and then got GCC, the GNU C compiler (now known as the GNU Compiler Collection, as it has been extended to compile various flavors of C, Fortran, Java, and Ada) working. At that stage, the kernel plus shell plus compiler was enough to be able to “bootstrap” the system — it could be used to build a copy of itself.

Torvalds’ Newsgroup Post

On August 25, 1991, Torvalds posted the following to the MINIX newsgroup comp.os.minix:

From: (Linus Benedict Torvalds) To: Newsgroups: comp.os.minix Subject: What would you like to see most in minix? Summary: small poll for my new operating system

Hello everybody out there 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-sytem due to practical reasons) among other things.

I’ve currently ported ...

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