Musl

Last updated
musl
Developer(s) Rich Felker (dalias) and others
Initial releaseFebruary 11, 2011;13 years ago (2011-02-11) [1]
Stable release
1.2.4 [2] / May 1, 2023;10 months ago (2023-05-01)
Repository
Operating system Linux 2.6 or later
Platform x86, x86_64, ARM, MIPS, Microblaze, PowerPC, powerpc64, x32, riscv64, OpenRISC, s390x, SuperH
Type
License MIT License
Website musl.libc.org

musl is a C standard library intended for operating systems based on the Linux kernel, released under the MIT License. [3] It was developed by Rich Felker to write a clean, efficient, and standards-conformant libc implementation. [4]

Contents

Overview

musl was designed from scratch to allow efficient static linking and to have realtime-quality robustness by avoiding race conditions, internal failures on resource exhaustion, and various other bad worst-case behaviors present in existing implementations. [4] The dynamic runtime is a single file with stable ABI allowing race-free updates and the static linking support allows an application to be deployed as a single portable binary without significant size overhead.

It claims compatibility with the POSIX 2008 specification and the C11 standard. It also implements most of the widely used non-standard Linux, BSD, and glibc functions. [5] There is partial ABI compatibility with the part of glibc required by Linux Standard Base. [6]

Version 1.2.0 has support for (no longer current) Unicode 12.1.0 (while still having full UTF-8 support, [7] more conformant/strict than glibc), and version 1.2.1 "features the new 'mallocng' malloc implementation, replacing musl's original dlmalloc-like allocator that suffered from fundamental design problems." [2]

Use

Some Linux distributions that can use musl as the standard C library include Alpine Linux, [8] Dragora 3, [9] Gentoo Linux, [10] OpenWrt, [11] Sabotage, [12] Morpheus Linux, [13] Chimera Linux, [14] and Void Linux. [15] The seL4 microkernel [16] ships with musl. For binaries that have been linked against glibc, gcompat [17] can be used to execute them on musl-based distros.

See also

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References

  1. ↑ "musl - obsolete versions". musl-libc.org. 2017-10-31. Retrieved 2018-01-14.>
  2. 1 2 "musl libc Release History". musl.libc.org. Archived from the original on 2021-10-16. Retrieved 2020-08-13.
  3. ↑ Rich Felker; et al. (2016-04-29). "COPYRIGHT". Archived from the original on 2021-10-16. Retrieved 2016-09-26.
  4. 1 2 "Introduction to musl". 2016-04-21. Archived from the original on 2021-10-16. Retrieved 2016-09-26.
  5. ↑ "Compatibility". wiki.musl-libc.org. 2014-05-27. Archived from the original on 2021-10-16. Retrieved 2016-09-26.
  6. ↑ "Comparison of C/POSIX standard library implementations for Linux". www.etalabs.net. Archived from the original on 2021-10-16.
  7. ↑ "musl libc - Functional differences from glibc". wiki.musl-libc.org. Archived from the original on 2021-10-16. Retrieved 2020-08-13.
  8. ↑ "About". Alpine Linux. Retrieved 18 June 2022.
  9. ↑ Larabel, Michael (30 September 2018). "Dragora 3.0 Alpha 2 Released As One Of The Libre GNU/Linux Platforms". Phoronix. Phoronix Media. Retrieved 18 June 2022.
  10. ↑ Gentoo Authors (20 July 2021). "Additional stage downloads for amd64, ppc, x86, arm available". Gentoo Linux. Retrieved 18 June 2022.
  11. ↑ Fietkau, Felix (16 Jun 2015). "OpenWrt switches to musl by default". Archived from the original on 28 July 2015.
  12. ↑ README.md on GitHub
  13. ↑ "morpheus". Archived from the original on 2021-10-16. Retrieved 2018-06-15.
  14. ↑ "Chimera Linux - About". Chimera Linux. Retrieved 2023-05-10.
  15. ↑ "Enter the void". Void Linux. Retrieved 18 June 2022.
  16. ↑ seL4/musllibc, seL4 microkernel and related repositories, 2020-08-30, archived from the original on 2021-10-16, retrieved 2020-09-05
  17. ↑ "Adélie Linux / gcompat". GitLab. Archived from the original on 2021-10-16. Retrieved 2019-10-21.


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