The `$os.skip` file describes tests that are to be skipped completely on the given OS.
Usually it is because of OS specific libraries.
+The `turing.skip` file describes tests that are to be skipped completely on the Turing cluster doing continuous testing over MPI.
+Usually it is because of an unavailable library or a large work which would not benefit from parallelization.
+
These `*.skip` files contain a list of patterns that will be used against test names.
A single substring can thus be used to skip a full family of tests.