Rust Essentials - Second Edition

Interfacing with C

Because of the vast functionality that exists in C code, it can sometimes be useful to delegate processing to a C routine, instead of writing everything in Rust.

You can call all functions and types from the C standard library by using the libc crate, which must be obtained through Cargo.

You have to add the following to Cargo.toml:

 [dependencies] 
    libc = "*" 

If you use Rust's nightly version, this is not necessary, but you have to use a feature attribute (or a feature gate, as they are also called) at the start of your code:

    #![feature(libc)]

Feature gates are common in Rust to enable the use of a certain functionality, but they are not available in stable Rust, only in the current development branch (nightly release). ...