cbindgen

TLDR

Generate C header from Rust library

$ cbindgen -o [header.h]

Generate C++ header

$ cbindgen --lang c++ -o [header.hpp]

Generate C header explicitly

$ cbindgen --lang c -o [header.h]

Use specific config file

$ cbindgen --config [cbindgen.toml] -o [header.h]

Generate from specific crate

$ cbindgen --crate [crate_name] -o [header.h]

Show help

$ cbindgen --help

SYNOPSIS

cbindgen [options] [cratedirectory_]

cbindgen generates C and C++11 headers from Rust libraries that expose a public C API. It parses Rust source code and creates corresponding C declarations for FFI-exported types and functions.
Developed by Mozilla, it ensures generated headers match Rust's type layout and ABI guarantees.

PARAMETERS

-o, --output file

Output header file path

--lang language

Output language: c or c++ (default: c++)

--config file

Path to cbindgen.toml configuration

--crate name

Crate name to generate bindings for

--profile name

Cargo profile to use

-v, --verbose

Enable verbose output

-q, --quiet

Suppress output

--verify

Verify existing header matches generated

--help

Show help

CONFIGURATION

Create cbindgen.toml for detailed configuration:

$ language = "C"
header = "/* Generated by cbindgen */"
include_guard = "MY_HEADER_H"

BUILD SCRIPT USAGE

Add to build.rs for automatic generation on build.

CAVEATS

Only generates headers for pub extern "C" functions and #[repr(C)] types. Requires proper FFI annotations in Rust code. Configuration file customizes output format.