Comment by muvlon

Comment by muvlon 4 days ago

9 replies

The first and foremost interface of the kernel is the syscall interface aka the uapi. libc and other C libraries like liburing or libcap are downstream of that. Many syscalls still don't have wrappers in libc after years of use.

samus 4 days ago

Yet for many syscalls there is an official library - in most cases a wrapper in libc, but especially io_uring is known to provide a C library that most applications ought to use instead of the raw syscalls.

smartmic 4 days ago

Thanks for clarification! I meant more, why isn't there a C API first, but Rust, Haskell, and Go before that — that's kind of surprising or new to me.

  • wging 4 days ago

    I read the article as saying that there's no official C library but unofficial ones do exist. Quote below, emphasis mine.

    > A official c library doesn’t exist yet unfortunately, but there’s several out there you can try.

    Also, it looks like there is more than zero support for C programs calling Landlock APIs. Even without a 3rd-party library you're not just calling syscall() with a magic number:

    https://docs.kernel.org/userspace-api/landlock.html

    https://github.com/torvalds/linux/blob/6bda50f4/include/uapi...

    https://github.com/torvalds/linux/blob/6bda50f4/include/linu...

  • WJW 4 days ago

    I don't understand what you mean. There's no "official" Rust, Haskell and Go APIs for this thing either. All libraries available seem to be just what some third party made available. There's also several C libraries, just none that have been officially endorsed by the Linux kernel team.

  • nine_k 4 days ago

    Go is famous for not needing libc and talking to the kernel. Rust and Haskell have communities that are very interested in safety and security, so they are earlier adopters.

    For C, unofficial support apparently sufficed for now.