Hi Julia There’s a couple different options depending on your use case. If you just need basic non-OS libc functionality (memcpy, string operations etc) then newlibc [1] should work. This can be quicker to setup as it is distributed with embedded toolchains. For example on ARM, the aarch64-none-elf- toolchain contains libc pre-compiled [2] and just requires a couple functions to be provided by the user, which can be left empty, see [3] for an example of that. I’m not sure to what extent newlibc provides POSIX functionality. For something closer to what you would see on something like Linux, musllibc is probably your best option that is what we use with LionsOS right now. The main caveat is that to get that kind of functionality you need a decent amount of OS services, which Microkit does not provide (hence why we only use musllibc within LionsOS). In LionsOS we used libnfs to get a network file system (NFS) working, which required POSIX functionality. To see what it looks like to get that working with musllibc and our OS services, have a look at [4]. Hope this helps. Ivan [1]: https://sourceware.org/newlib/ [2]: https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads [3]: https://github.com/au-ts/sddf/blob/main/util/newlibc.c [4]: https://github.com/au-ts/lionsos/blob/main/components/fs/nfs/posix.c On 5 May 2025, at 22:12, Julia Royer via Devel <devel@sel4.systems> wrote: Hello, I'm currently developing a simple communication application to explore seL4 and Microkit, and I'd like to use a C standard library (libc) in my project. I came across libsel4muslcsys and the seL4/musllibc repository. Are there any other components I should be aware of? Also, is there a specific way to integrate these into my project? Thank you for your help. Best regards, Julia Royer _______________________________________________ Devel mailing list -- devel@sel4.systems To unsubscribe send an email to devel-leave@sel4.systems