<-d -4> is not a valid option
usage: h5diff [OPTIONS] file1 file2 [obj1[obj2]] 
  file1                    File name of the first HDF5 file
  file2                    File name of the second HDF5 file
  [obj1]                   Name of an HDF5 object, in absolute path
  [obj2]                   Name of an HDF5 object, in absolute path

  OPTIONS
   -h, --help              Print a usage message and exit.
   -V, --version           Print version number and exit.
   -r, --report            Report mode. Print differences.
   -v, --verbose           Verbose mode. Print differences, list of objects.
   -q, --quiet             Quiet mode. Do not produce output.
   --follow-links          Follow symbolic links (soft links and external links)
                           and compare the links' target objects.
                           If symbolic link(s) with the same name exist in the
                           files being compared, then determine whether the 
                           target of each link is an existing object (dataset,
                           group, or named datatype) or the link is a dangling
                           link (a soft or external link pointing to a target
                           object that does not yet exist).
                           - If both symbolic links are dangling links, they
                             are treated as being the same; by default, h5diff
                             returns an exit code of 0. If, however, 
                             --no-dangling-links is used with --follow-links, 
                             this situation is treated as an error and h5diff 
                             returns an exit code of 2.
                           - If only one of the two links is a dangling link,
                             they are treated as being different and h5diff 
                             returns an exit code of 1. If, however, 
                             --no-dangling-links is used with --follow-links, 
                             this situation is treated as an error and h5diff 
                             returns an exit code of 2.
                           - If both symbolic links point to existing objects,
                             h5diff compares the two objects.
                           If any symbolic link specified in the call to h5diff
                           does not exist, h5diff treats it as an error and
                           returns an exit code of 2.
   --no-dangling-links     Must be used with --follow-links option;
                           otherwise, h5diff shows error message and returns
                           an exit code of 2.
                           Check for any symbolic links (soft links or external
                           links) that do not resolve to an existing object
                           (dataset, group, or named datatype).  If any
                           dangling link is found, this situation is treated as
                           an error and h5diff returns an exit code of 2.
   -c, --compare           List objects that are not comparable
   -N, --nan               Avoid NaNs detection
   -n C, --count=C         Print differences up to C number, C is a positive
                           integer.
   -d D, --delta=D         Print difference if (|a-b| > D), D is a positive
                           number.
   -p R, --relative=R      Print difference if (|(a-b)/b| > R), R is a positive
                           number.
   --use-system-epsilon    Print difference if (|a-b| > EPSILON),
                           where EPSILON (FLT_EPSILON or FLT_EPSILON) is the
                           system epsilon value. 
                           If the system epsilon is not defined, use the value
                           below:
                               FLT_EPSILON = 1.19209E-07 for float
                               DBL_EPSILON = 2.22045E-16 for double
                           -d, -p, and --use-system-epsilon options are used for
                           comparing floating point values.
                           By default, strict equality is used. Use -p or -d to
                           set specific tolerance.

 Modes of output:
  Default mode: print the number of differences found and where they occured
  -r Report mode: print the above plus the differences
  -v Verbose mode: print the above plus a list of objects and warnings
  -q Quiet mode: do not print output

 Compare criteria
  If no objects [obj1[obj2]] are specified, h5diff only compares objects
  with the same absolute path in both files

 The compare criteria is:
  1) datasets: numerical array differences
  2) groups: name string difference
  3) datatypes: the return value of H5Tequal
  4) links: name string difference of the linked value as default
            (refer to --follow-links option).

 Exit code:
  0 if no differences, 1 if differences found, 2 if error

 Examples of use:
 1) h5diff file1 file2 /g1/dset1 /g1/dset2
    Compares object '/g1/dset1' in file1 with '/g1/dset2' in file2

 2) h5diff file1 file2 /g1/dset1
    Compares object '/g1/dset1' in both files

 3) h5diff file1 file2
    Compares all objects in both files

 Notes:
  file1 and file2 can be the same file.
  Use h5diff file1 file1 /g1/dset1 /g1/dset2 to compare
  '/g1/dset1' and '/g1/dset2' in the same file

EXIT CODE: 1