The isELF function only checks whether ELF is contained within the first
4 bytes of the file, which is a bit fuzzy and will also return
successful if it's a text file starting with ELF, for example:
ELF headers
-----------
Some text here about ELF headers...
So instead, we're now doing a precise match on \x7fELF.
Signed-off-by: aszlig <aszlig@nix.build>
Acked-by: @Ericson2314
Closes: https://github.com/NixOS/nixpkgs/pull/47244
b25b6e0c75