read_to_string in std::fs - Rust (original) (raw)

Function read_to_string

1.26.0 · Source

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

Expand description

Reads the entire contents of a file into a string.

This is a convenience function for using File::open and read_to_stringwith fewer imports and without an intermediate variable.

§Errors

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

If the contents of the file are not valid UTF-8, then an error will also be returned.

While reading from the file, this function handles io::ErrorKind::Interruptedwith automatic retries. See io::Read documentation for details.

§Examples

use std::fs;
use std::error::Error;

fn main() -> Result<(), Box<dyn Error>> {
    let message: String = fs::read_to_string("message.txt")?;
    println!("{}", message);
    Ok(())
}