posix-next

The next-generation of Zephyr's POSIX reference design.

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What is posix-next?

posix-next is an out-of-tree Zephyr RTOS module that serves as a staging tree for upstream POSIX API features. It tracks ahead of what is upstream and aims to improve the cadence of feature development and testing. In terms of confromance, posix-next targets the POSIX.1-2018 release (Issue 7), although there is some support for POSIX.1-2024 (Issue 8).

Key goals:

• Portability — run POSIX applications on Zephyr with minimal changes.
• Conformance — track the full POSIX option groups and work toward PSE51/52/53 profiles.
• Linux parity — validate behavior against Linux using native_sim and real hardware.

Documentation

Resource	Link
Guides & overview	cfriedt.github.io/posix-next
Getting started	Getting Started
API reference (Doxygen)	Doxygen HTML
POSIX symbol search	Symbol search
Option groups	Option groups
Conformance status	Conformance

Quick start

See the full Getting Started guide for workspace setup, SDK installation, and sample applications.

Repository layout

modules/lib/posix/
├── doc/                    # Sphinx documentation sources
│   ├── posix/              # Vendored POSIX guides (from Zephyr v4.3.0)
│   └── _static/            # Logo, CSS
├── include/zephyr/posix/   # Public POSIX headers (Doxygen documented)
├── lib/posix/options/      # Implementation sources
├── samples/posix/          # Example applications
├── tests/                  # Test suites (Twister)
└── west.yml                # West manifest (pins Zephyr v4.3.0)

Contributing

Contributions are welcome! Please open an issue or pull request on GitHub.

License

This project is licensed under the Apache License 2.0.