The last 2 lines of output of e.g. nix-build --hash -A fio.src with a random sha256 value are:
build produced path ‘/nix/store/1ddvn536mgycflb48m23r8w4d01bzvkq-fio-fio-2.12-src’ with sha256 hash ‘1m0fx0x1v2375vyxhd2i12b9w1qy4yh75f6qhwlcr78himcsmpp9’
/nix/store/bcmckd9vn7gyrdyic5lyic01b5j3a5l2-fio-fio-2.12-src
That is, the useful value, 1m0fx0x1v2375vyxhd2i12b9w1qy4yh75f6qhwlcr78himcsmpp9 is only present in the stderr/build log. The line printed to stdout (the last one) is actually useless as it's presumably the "temporary" output path used before the hash is known.
The last 2 lines of output of e.g.
nix-build --hash -A fio.srcwith a randomsha256value are:That is, the useful value,
1m0fx0x1v2375vyxhd2i12b9w1qy4yh75f6qhwlcr78himcsmpp9is only present in the stderr/build log. The line printed to stdout (the last one) is actually useless as it's presumably the "temporary" output path used before the hash is known.