When running our Jenkins pipeline we sometimes get errors like the one below and there I would like to know what clues the directory path can give me.

/machine01/jenkins_ws/nfs_ws/01/workspace/main-ci-job/path/in/repo@tmp/durable-82d83e2b/script.sh.copy: line 3: cmake: command not found

So in this case we have a CMakeLists.txt file in path/in/repo, but what does @tmp/durable-82d83e2b mean?

1. What is @tmp?
2. What is durable?
3. What is the hash? (it is not a hash known to git)