1libc 2==== 3 4A Rust library with native bindings to the types and functions commonly found on 5various systems, including libc. 6 7[](https://travis-ci.org/rust-lang/libc) 8[](https://ci.appveyor.com/project/rust-lang-libs/libc) 9 10[Documentation](#platforms-and-documentation) 11 12## Usage 13 14First, add the following to your `Cargo.toml`: 15 16```toml 17[dependencies] 18libc = "0.2" 19``` 20 21Next, add this to your crate root: 22 23```rust 24extern crate libc; 25``` 26 27Currently libc by default links to the standard library, but if you would 28instead like to use libc in a `#![no_std]` situation or crate you can request 29this via: 30 31```toml 32[dependencies] 33libc = { version = "0.2", default-features = false } 34``` 35 36## What is libc? 37 38The primary purpose of this crate is to provide all of the definitions necessary 39to easily interoperate with C code (or "C-like" code) on each of the platforms 40that Rust supports. This includes type definitions (e.g. `c_int`), constants 41(e.g. `EINVAL`) as well as function headers (e.g. `malloc`). 42 43This crate does not strive to have any form of compatibility across platforms, 44but rather it is simply a straight binding to the system libraries on the 45platform in question. 46 47## Public API 48 49This crate exports all underlying platform types, functions, and constants under 50the crate root, so all items are accessible as `libc::foo`. The types and values 51of all the exported APIs match the platform that libc is compiled for. 52 53More detailed information about the design of this library can be found in its 54[associated RFC][rfc]. 55 56[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/1291-promote-libc.md 57 58## Adding an API 59 60Want to use an API which currently isn't bound in `libc`? It's quite easy to add 61one! 62 63The internal structure of this crate is designed to minimize the number of 64`#[cfg]` attributes in order to easily be able to add new items which apply 65to all platforms in the future. As a result, the crate is organized 66hierarchically based on platform. Each module has a number of `#[cfg]`'d 67children, but only one is ever actually compiled. Each module then reexports all 68the contents of its children. 69 70This means that for each platform that libc supports, the path from a 71leaf module to the root will contain all bindings for the platform in question. 72Consequently, this indicates where an API should be added! Adding an API at a 73particular level in the hierarchy means that it is supported on all the child 74platforms of that level. For example, when adding a Unix API it should be added 75to `src/unix/mod.rs`, but when adding a Linux-only API it should be added to 76`src/unix/notbsd/linux/mod.rs`. 77 78If you're not 100% sure at what level of the hierarchy an API should be added 79at, fear not! This crate has CI support which tests any binding against all 80platforms supported, so you'll see failures if an API is added at the wrong 81level or has different signatures across platforms. 82 83With that in mind, the steps for adding a new API are: 84 851. Determine where in the module hierarchy your API should be added. 862. Add the API. 873. Send a PR to this repo. 884. Wait for CI to pass, fixing errors. 895. Wait for a merge! 90 91### Test before you commit 92 93We have two automated tests running on [Travis](https://travis-ci.org/rust-lang/libc): 94 951. [`libc-test`](https://github.com/alexcrichton/ctest) 96 - `cd libc-test && cargo test` 97 - Use the `skip_*()` functions in `build.rs` if you really need a workaround. 982. Style checker 99 - `rustc ci/style.rs && ./style src` 100 101### Releasing your change to crates.io 102 103Now that you've done the amazing job of landing your new API or your new 104platform in this crate, the next step is to get that sweet, sweet usage from 105crates.io! The only next step is to bump the version of libc and then publish 106it. If you'd like to get a release out ASAP you can follow these steps: 107 1081. Update the version number in `Cargo.toml`, you'll just be bumping the patch 109 version number. 1102. Run `cargo update` to regenerate the lockfile to encode your version bump in 111 the lock file. You may pull in some other updated dependencies, that's ok. 1123. Send a PR to this repository. It should [look like this][example], but it'd 113 also be nice to fill out the description with a small rationale for the 114 release (any rationale is ok though!) 1154. Once merged the release will be tagged and published by one of the libc crate 116 maintainers. 117 118[example]: https://github.com/rust-lang/libc/pull/583 119 120## Platforms and Documentation 121 122The following platforms are currently tested and have documentation available: 123 124Tested: 125 * [`i686-pc-windows-msvc`](https://doc.rust-lang.org/libc/i686-pc-windows-msvc/libc/) 126 * [`x86_64-pc-windows-msvc`](https://doc.rust-lang.org/libc/x86_64-pc-windows-msvc/libc/) 127 (Windows) 128 * [`i686-pc-windows-gnu`](https://doc.rust-lang.org/libc/i686-pc-windows-gnu/libc/) 129 * [`x86_64-pc-windows-gnu`](https://doc.rust-lang.org/libc/x86_64-pc-windows-gnu/libc/) 130 * [`i686-apple-darwin`](https://doc.rust-lang.org/libc/i686-apple-darwin/libc/) 131 * [`x86_64-apple-darwin`](https://doc.rust-lang.org/libc/x86_64-apple-darwin/libc/) 132 (OSX) 133 * `i386-apple-ios` 134 * `x86_64-apple-ios` 135 * [`i686-unknown-linux-gnu`](https://doc.rust-lang.org/libc/i686-unknown-linux-gnu/libc/) 136 * [`x86_64-unknown-linux-gnu`](https://doc.rust-lang.org/libc/x86_64-unknown-linux-gnu/libc/) 137 (Linux) 138 * [`x86_64-unknown-linux-musl`](https://doc.rust-lang.org/libc/x86_64-unknown-linux-musl/libc/) 139 (Linux MUSL) 140 * [`aarch64-unknown-linux-gnu`](https://doc.rust-lang.org/libc/aarch64-unknown-linux-gnu/libc/) 141 (Linux) 142 * [`aarch64-unknown-linux-musl`](https://doc.rust-lang.org/libc/aarch64-unknown-linux-musl/libc/) 143 (Linux MUSL) 144 * [`mips-unknown-linux-gnu`](https://doc.rust-lang.org/libc/mips-unknown-linux-gnu/libc/) 145 * [`arm-unknown-linux-gnueabihf`](https://doc.rust-lang.org/libc/arm-unknown-linux-gnueabihf/libc/) 146 * [`arm-linux-androideabi`](https://doc.rust-lang.org/libc/arm-linux-androideabi/libc/) 147 (Android) 148 * [`x86_64-unknown-freebsd`](https://doc.rust-lang.org/libc/x86_64-unknown-freebsd/libc/) 149 * [`x86_64-unknown-openbsd`](https://doc.rust-lang.org/libc/x86_64-unknown-openbsd/libc/) 150 * [`x86_64-rumprun-netbsd`](https://doc.rust-lang.org/libc/x86_64-unknown-netbsd/libc/) 151 152The following may be supported, but are not guaranteed to always work: 153 154 * `i686-unknown-freebsd` 155 * [`x86_64-unknown-bitrig`](https://doc.rust-lang.org/libc/x86_64-unknown-bitrig/libc/) 156 * [`x86_64-unknown-dragonfly`](https://doc.rust-lang.org/libc/x86_64-unknown-dragonfly/libc/) 157 * `i686-unknown-haiku` 158 * `x86_64-unknown-haiku` 159 * [`x86_64-unknown-netbsd`](https://doc.rust-lang.org/libc/x86_64-unknown-netbsd/libc/) 160
){kind=link}