Display the default hints for a file system.
MPI-IO uses "hints" as ways for users to tell the MPI-IO routines something about the anticipated workload. MPI-IO implementations use hints to tune internal algorithms. In practice, not many users set hints but they can have a big impact on perfromamce sometimes.
This simple little utility has been way more useful than I expected. Knowing something about the default hints also helps confirm my own assumptions about what's going on inside the MPI-IO library.
hintdump <filename>
<filename> can be a directory