errno 
Cross-platform interface to the errno variable. Works on Rust 1.13 or newer.
Documentation is available at https://docs.rs/errno.
Dependency
Add to your Cargo.toml:
[dependencies]
errno = "*"Examples
extern crate errno;
use errno::{Errno, errno, set_errno};
// Get the current value of errno
let e = errno();
// Set the current value of errno
set_errno(e);
// Extract the error code as an i32
let code = e.0;
// Display a human-friendly error message
println!("Error {}: {}", code, e);#![no_std]
Enable #![no_std] support by disabling the default std feature:
[dependencies]
errno = { version = "*", default-features = false }The Debug and Display impls will be unavailable.