1 use flate2::write::GzEncoder; 2 use flate2::Compression; 3 use std::env::args; 4 use std::fs::File; 5 use std::io::copy; 6 use std::io::BufReader; 7 use std::time::Instant; 8 main()9fn main() { 10 if args().len() != 3 { 11 eprintln!("Usage: ./compress_file `source` `target`"); 12 return; 13 } 14 let mut input = BufReader::new(File::open(args().nth(1).unwrap()).unwrap()); 15 let output = File::create(args().nth(2).unwrap()).unwrap(); 16 let mut encoder = GzEncoder::new(output, Compression::default()); 17 let start = Instant::now(); 18 copy(&mut input, &mut encoder).unwrap(); 19 let output = encoder.finish().unwrap(); 20 println!( 21 "Source len: {:?}", 22 input.get_ref().metadata().unwrap().len() 23 ); 24 println!("Target len: {:?}", output.metadata().unwrap().len()); 25 println!("Elapsed: {:?}", start.elapsed()); 26 } 27