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use crate::fs::asyncify; use std::{io, path::Path}; /// Reads the entire contents of a file into a bytes vector. /// /// This is an async version of [`std::fs::read`][std] /// /// [std]: std::fs::read /// /// This is a convenience function for using [`File::open`] and [`read_to_end`] /// with fewer imports and without an intermediate variable. It pre-allocates a /// buffer based on the file size when available, so it is generally faster than /// reading into a vector created with `Vec::new()`. /// /// [`File::open`]: super::File::open /// [`read_to_end`]: crate::io::AsyncReadExt::read_to_end /// /// # Errors /// /// This function will return an error if `path` does not already exist. /// Other errors may also be returned according to [`OpenOptions::open`]. /// /// [`OpenOptions::open`]: super::OpenOptions::open /// /// It will also return an error if it encounters while reading an error /// of a kind other than [`ErrorKind::Interrupted`]. /// /// [`ErrorKind::Interrupted`]: std::io::ErrorKind::Interrupted /// /// # Examples /// /// ```no_run /// use tokio::fs; /// use std::net::SocketAddr; /// /// #[tokio::main] /// async fn main() -> Result<(), Box<dyn std::error::Error + 'static>> { /// let contents = fs::read("address.txt").await?; /// let foo: SocketAddr = String::from_utf8_lossy(&contents).parse()?; /// Ok(()) /// } /// ``` pub async fn read(path: impl AsRef<Path>) -> io::Result<Vec<u8>> { let path = path.as_ref().to_owned(); asyncify(move || std::fs::read(path)).await }