[Nix-dev] nix-prefetch-url and sha256sum differs

[Bjørn Forsman]

Hi,

nix-prefetch-url returns a different sha256 hash than the sha256sum
command. This is rather confusing.

For example, I want to update lighttpd. I go to their website and see
that the lighttpd-1.4.32.tar.gz should have sha256 sum
0765e07dac432393dea3950639d5ba646ded95a9408ad002e54b3353ab6b9645. But
this is what nix-prefetch-url says:

$ nix-prefetch-url --type sha256
http://download.lighttpd.net/lighttpd/releases-1.4.x/lighttpd-1.4.32.tar.gz
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  826k  100  826k    0     0   827k      0 --:--:-- --:--:-- --:--:--  828k
path is ‘/nix/store/6alqcyg5qayvwv90vqay1kqxq40mqmm0-lighttpd-1.4.32.tar.gz’
0icndfmm6csbwl1d12j0m6aysvb4pbakj1lmlgg968s3miyy0r87

When I run sha256sum on the downloaded file I get the correct result:

$ sha256sum /nix/store/6alqcyg5qayvwv90vqay1kqxq40mqmm0-lighttpd-1.4.32.tar.gz
0765e07dac432393dea3950639d5ba646ded95a9408ad002e54b3353ab6b9645
/nix/store/6alqcyg5qayvwv90vqay1kqxq40mqmm0-lighttpd-1.4.32.tar.gz

Why is this happening?

Best regards,
Bjørn Forsman