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Function std::fs::read_to_string

pub fn read_to_string<P: AsRef<Path>>(path: P) -> Result<String>

Read the entire contents of a file into a string.

This is a convenience function for using File::open and read_to_string 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 string created with String::new().

Errors

This function will return an error if path does not already exist. Other errors may also be returned according to OpenOptions::open.

It will also return an error if it encounters while reading an error of a kind other than ErrorKind::Interrupted, or if the contents of the file are not valid UTF-8.

Examples

use std::fs;
use std::net::SocketAddr;

fn main() -> Result<(), Box<dyn std::error::Error + 'static>> {
    let foo: SocketAddr = fs::read_to_string("address.txt")?.parse()?;
    Ok(())
}

© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/fs/fn.read_to_string.html