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At my university, students in groups of 1 or 2 write a fully preemptible, multiprocessor unixy kernel and userspace on x86. Essentially nothing is provided exce

by gosu 14y ago

At my university, students in groups of 1 or 2 write a fully preemptible, multiprocessor unixy kernel and userspace on x86. Essentially nothing is provided except a bootloader, a build system, a syscall spec, and some moderate protection from the details of some hardware beyond the CPU. This is considered doable in a semester by college students, some of who have no preparation except a general "here's what a CPU register is, here's what caching is" course. No one reads 20-30 books, but rather most students work from first principles and wind up reinventing the usual algorithms on their own. I thought I'd offer a more optimistic counterpoint. I think that the 10,000 hours figure is way, way overestimating the amount of time needed in order to create something usable enough to make you satisfied, and which could teach you enough to understand any real operating system at the level of source code. Although, yeah, if you've got commercial aspirations like OP, then I think you're in for it.

robomartin 14y ago
> Although, yeah, if you've got commercial aspirations like OP, then I think you're in for it. I think you nailed it right there. If the OP had said something akin to "I want to write a small OS with a command line interface to learn about the topic" it would have been an entirely different question. I would encourage anyone to do that. It would be an excellent learning experience and the foundation for a lot more interesting work. If you go back and read the post, this is no small OS any of of the many sub-projects he is proposing is a huge undertaking for a developer who self-describes this way: "I spend most of my days in the world of PHP, JavaScript (I love jQuery) and a little bit of HTML, CSS and ActionScript 3.0". With regards to your comment about writing a "fully preemptible, multiprocessor unixy kernel and userspace on x86" in school. Sure. Of course. But, keep in mind that you are actually being TAUGHT how to do this and guided throughout the process. You also mentioned that "a bootloader, a build system, a syscall spec, and some moderate protection from the details of some hardware beyond the CPU" are provided. The OP is talking about writing everything! For example, he seems to talk about writing PCIe, SATA and USB interfaces. That alone could take a newbie a whole year to figure out. Particularly if coming from being a web developer. Insane? Yes. Impossible? Of course not. Probable? Nope.
- gosu 14y ago
  Agreed. I just wanted to talk in general to make sure that people weren't too intimidated. I think a hobby OS is a great way to become a better programmer. About the course: the extent to which we were guided was minimal by design. It wasn't a matter of "here's a skeleton, here are steps A, B, and C to get it working", but rather "here's an API, implement it; here are some general design ideas". I think that this is comparable to what you'd get if you sat down with a book on your own, and so I hope that it might give people a decent idea of the level of difficulty of such a project. I emphatically agree with your point about the difficulty of a newbie + PCI situation, although a year still seems steep.

by gosu 14y ago

robomartin 14y ago

> Although, yeah, if you've got commercial aspirations like OP, then I think you're in for it. I think you nailed it right there. If the OP had said something akin to "I want to write a small OS with a command line interface to learn about the topic" it would have been an entirely different question. I would encourage anyone to do that. It would be an excellent learning experience and the foundation for a lot more interesting work. If you go back and read the post, this is no small OS any of of the many sub-projects he is proposing is a huge undertaking for a developer who self-describes this way: "I spend most of my days in the world of PHP, JavaScript (I love jQuery) and a little bit of HTML, CSS and ActionScript 3.0". With regards to your comment about writing a "fully preemptible, multiprocessor unixy kernel and userspace on x86" in school. Sure. Of course. But, keep in mind that you are actually being TAUGHT how to do this and guided throughout the process. You also mentioned that "a bootloader, a build system, a syscall spec, and some moderate protection from the details of some hardware beyond the CPU" are provided. The OP is talking about writing everything! For example, he seems to talk about writing PCIe, SATA and USB interfaces. That alone could take a newbie a whole year to figure out. Particularly if coming from being a web developer. Insane? Yes. Impossible? Of course not. Probable? Nope.

gosu 14y ago
Agreed. I just wanted to talk in general to make sure that people weren't too intimidated. I think a hobby OS is a great way to become a better programmer. About the course: the extent to which we were guided was minimal by design. It wasn't a matter of "here's a skeleton, here are steps A, B, and C to get it working", but rather "here's an API, implement it; here are some general design ideas". I think that this is comparable to what you'd get if you sat down with a book on your own, and so I hope that it might give people a decent idea of the level of difficulty of such a project. I emphatically agree with your point about the difficulty of a newbie + PCI situation, although a year still seems steep.