1 use std::{
2     error::Error,
3     fs::File,
4     io::{self, Seek, SeekFrom},
5 };
6 
main() -> Result<(), Box<dyn Error>>7 fn main() -> Result<(), Box<dyn Error>> {
8     let mut file = File::open("bar.txt")?;
9 
10     assert_eq!(27, file.metadata()?.len());
11 
12     assert_eq!(
13         "And stood awhile in thought",
14         &io::read_to_string(&mut file)?
15     );
16 
17     file.seek(SeekFrom::Start(11))?;
18 
19     assert_eq!("while in thought", &io::read_to_string(&mut file)?);
20 
21     Ok(())
22 }
23