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Expected output for 'hdiff '
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hdiff [-b] [-g] [-s] [-d] [-S] [-v ...] [-e counnt] [-t limit] file1 file2
  [-b]              Verbose mode
  [-g]              Compare global attributes only
  [-s]              Compare SD local attributes only
  [-d]              Compare SD data only
  [-D]              Compare Vdata data only
  [-S]              Print statistics
  [-v var1[,...]]   Compare SD data on variable(s) <var1>,... only
  [-u var1[,...]]   Compare vdata on variable(s) <var1>,... only
  [-e count]        Print difference up to count number for each variable
  [-t limit]        Print difference when it is greater than limit
  file1             File name of the first input HDF file
  file2             File name of the second input HDF file
