liblinux VS Mezzano

> libc isn't really getting in the way here.

For the standard set of system calls, the libc is pretty great. For Linux-specific features, it could take years for glibc to gain support. Perhaps it's gotten better since then, perhaps it still takes years. I don't know.

Years ago I read about the tale of the getrandom system call and the quest to get glibc to support it:

https://lwn.net/Articles/711013/

A kernel hacker wrote in an email:

> maybe the kernel developers should support a libinux.a library that would allow us to bypass glibc when they are being non-helpful

That made a lot of sense to me. I took that concept and kind of ran with it. Started a liblinux project, essentially a libc with nothing but the thinnest possible system call wrappers. Researched quite a bit about glibc's attitude towards Linux to justify it:

https://github.com/matheusmoreira/liblinux#why

Eventually I discovered Linux was already doing the same thing with their own nolibc.h file which they were already using in their own tools. It was a single file back then, by now it's become a sprawling directory full of code:

https://github.com/torvalds/linux/tree/master/tools/include/...

Even asked Greg Kroah-Hartman on reddit about it once:

https://old.reddit.com/r/linux/comments/fx5e4v/im_greg_kroah...

Since the kernel was developing their own awesome headers, I decided to drop liblinux and start lone instead. :)

It gives you access to 100% of Linux's system calls. It eliminates a lot of global state. It gets rid of a lot of legacy libc crap.

Years ago I wrote a fairly referenced rationale in my liblinux project:

https://github.com/matheusmoreira/liblinux/blob/master/READM...

> Now, do I think it would make total sense for syscall wrappers and NSS to be split into their own libs (or dbus interfaces maybe) with stable ABIs to enable other libc's, absolutely!

I worked on this a few years ago: liblinux.

https://github.com/matheusmoreira/liblinux

I'm not developing it anymore though because I found out the Linux kernel itself has a superior nolibc library:

https://github.com/torvalds/linux/tree/master/tools/include/...

It used to be a single header but it looks like they've recently organized it into a proper project!

I wonder if it will become some kind of official kernel library at some point. I asked Greg Kroah-Hartman about this and he mentioned there was once a klibc:

https://old.reddit.com/r/linux/comments/fx5e4v/im_greg_kroah...

> This is something the BSD's got absolutely right.

BSDs, every other operating system really, force us to use the bundled C libraries and the C ABI. I think Linux's approach is better. It has a language-agnostic system call binary interface: it's just a simple calling convention and the system call instruction.

The right place for system call support is the compiler. We should have system_call keywords that cause it to emit code in the aforementioned calling convention. With this single keyword, it's possible to do program literally anything on Linux. Wrappers for every specific system call should be part of every language's standard library with language-specific types and semantics.

I'm not using this stuff professionally, it's just my own home lab's virtual machines with little services implemented as freestanding C programs. Not doing anything fancy right now, much of it was just to see if I could do it.

I've seen other people commenting here on HN saying they're using the same approach so it's defenitely not my invention.

I published some of my work in the form of a liblinux that I use to make system calls:

https://github.com/matheusmoreira/liblinux

I'm not developing it anymore though because I found out the kernel itself has a nolibc library:

https://github.com/torvalds/linux/tree/master/tools/include/...

It used to be a single header but it looks like they've organized it into a proper project.

That's awesome. I didn't know about rwildcard until now. Is it part of GMSL? I searched for rwildcard on gmsl.sourceforge.io but didn't find it.

I think my function is needlessly complicated compared to rwildcard. Here's my code:

https://github.com/matheusmoreira/liblinux/blob/modular-buil...

https://github.com/matheusmoreira/liblinux/blob/modular-buil...

The file? and directory? functions were inspired by GMSL.

I wrote a general recursion function. It takes a function to apply to lists and a function to compute whether an element is a base case.

The recursive file system traversal function applies a directory globbing function to the list of paths and has file? as base case.

The find function filters out any items not matching a given predicate function. It was my intention to provide predicates like C_file? and header_file? but I stopped developing that project before that happened.

I think rwildcard is probably simpler and more efficient!

Have you made or plan to make any contributions to Mezzano (https://github.com/froggey/Mezzano) or are you mainly interested in seeing how far you can take this thing on your own?

>> except building compilers and OSes

SBCL is written in Lisp, yes? Except the runtime, which is C + asm.

I've heard people wrote some OSes in the past, like Genera. Or if you prefer recent attempt, try https://github.com/froggey/Mezzano. Never tried it, though.

No need to.

Not at all. See mezzano for a notable recent example of an OS written entirely in a dynamic language.

So..

"Why do you want to make Lisp more popular? If you were sucessful, what would be different in the world, and why is that desirable to you?"

Normally at this point I'd listen to the response, and ask more questions based on that. That would wind up with a very, very deep thread, so I'll break a cardinal rule and pre-guess at some answers.

This kind of question comes up pretty frequently. In many cases, I suspect the motivation behind the question is "Wow! Here's this cool tool I've discovered. I want to make something really useful with it. I want to do it as part of a community effort; share my excitement with others, share in their excitement, and know that what I'm making is useful because others find it desirable and are excited by it." The field could be cooking, sports, old machine tools, tiny homes, or demo scene. Its the fundemental driver for most content on HN, YouTube, Instructables, and such. It is a Good Thing.

If that is your motivator, then my suggestion is to find something that bugs you and fix it. You've already decided you're only interested in code, not other aspects. You said you preferred vim, but the emacs ecosystem has a very rich set of sharp edges that need filing off, and a rich set of tools with which to attack them.

One example: even after 50 years there's no open IDE which allows you to easily globally rename a Lisp identifier. I don't know about LispWorks or other proprietary environments, but you can't in emacs or vim do a right-click on "foo" in "(defun foo ()...)" and select a command which automatically renames it in all invocations. [Queue lots of "but you can..." replies here.] I don't think vim is up to the task of doing this internally. It would be possible in emacs; but would require a huge effort with lots of help from other people. If you emerged alive from that rabbit warren you'd join the company of Certified "How Hard Could it Be?" Mad Scientists such as Dr. "I just want to draw molecules" Meister [1] and "Wouldn't an OS in Lisp be Cool" Froggey [2].

[1] https://github.com/clasp-developers/clasp

[2] Mezzano https://github.com/froggey/Mezzano

You might want to look at Mezzano which is an operation system written in Common Lisp https://github.com/froggey/Mezzano

I haven’t tried it since moving to M1/ARM, but it is cool.