This is the reference documentation for the Zephyr RTOS C API: all the functions, macros, and data structures available to Zephyr applications and subsystems, generated directly from the source code.

Browse the API by topic

The API is organized as a hierarchy of Topics covering the main areas of the OS. Start with one of the main categories below, or browse the full topic list.

Kernel Threads, scheduling, synchronization, timers, and other core RTOS primitives. Device Drivers Hardware-agnostic interfaces for peripherals: GPIO, I2C, SPI, sensors, and more. Operating System Services Networking, Bluetooth, storage, logging, and other services built on the kernel. Devicetree Macros for reading the hardware description of the system at build time. Device Model The abstraction that binds drivers to the hardware instances they manage. Memory Management Heaps, memory slabs, and memory-mapping interfaces. Utilities General-purpose helpers, including the data structure APIs. Testing The Ztest framework and related testing helpers.

Other ways to explore

Data Structures: an index of all documented structs and unions.
Files: browse the API header by header.
Deprecated List: APIs scheduled for removal, and what to use instead.
Use the search box to find any documented symbol by name.

Looking for something else?

This site only covers the C API. For guides, samples, supported boards, and everything else, head over to the main Zephyr Project documentation.