Panic when cannot read file

[Mohammed Alotaibi]

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 13, kind: PermissionDenied, message: "Permission denied" }', /home/awiteb/.cargo/registry/src/github.com-1ecc6299db9ec823/checksums-0.9.1/src/hashing/mod.rs:63:39
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

$ csum -V
csum 0.1.1