63 lines
1.4 KiB
Markdown
63 lines
1.4 KiB
Markdown
# errno [](https://github.com/lambda-fairy/rust-errno/actions/workflows/main.yml) [](https://crates.io/crates/errno)
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Cross-platform interface to the [`errno`][errno] variable. Works on Rust 1.56 or newer.
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Documentation is available at <https://docs.rs/errno>.
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[errno]: https://en.wikipedia.org/wiki/Errno.h
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## Dependency
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Add to your `Cargo.toml`:
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```toml
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[dependencies]
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errno = "*"
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```
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## Comparison with `std::io::Error`
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The standard library provides [`Error::last_os_error`][last_os_error] which fetches `errno` in the same way.
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This crate provides these extra features:
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- No heap allocations
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- Optional `#![no_std]` support
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- A `set_errno` function
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[last_os_error]: https://doc.rust-lang.org/std/io/struct.Error.html#method.last_os_error
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## Examples
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```rust
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extern crate errno;
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use errno::{Errno, errno, set_errno};
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// Get the current value of errno
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let e = errno();
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// Set the current value of errno
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set_errno(e);
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// Extract the error code as an i32
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let code = e.0;
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// Display a human-friendly error message
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println!("Error {}: {}", code, e);
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```
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## `#![no_std]`
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Enable `#![no_std]` support by disabling the default `std` feature:
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```toml
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[dependencies]
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errno = { version = "*", default-features = false }
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```
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The `Error` impl will be unavailable.
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