The following scripts require "keys" for the tests to run correctly:

pairs.t
pairs-noroot.t
trace.t
utils/wnDepths.t

These scripts support two command-line options:
1) the --key option can be used to generate a key, in which case no actual
   tests are run.
2) the --keydir option can be used to specify where the key is or should be
   stored.  The default value is t/keys.