Opened "1_vds.h5" with sec2 driver.
vds_dset                 Dataset {5/Inf, 18/18, 8/8}
    Location:  1:800
    Links:     1
    Maps:      {6} Source {
                      1_a.h5   /source_dset
                      1_b.h5   /source_dset
                      1_c.h5   /source_dset
                      1_d.h5   /source_dset
                      1_e.h5   /source_dset
                      1_f.h5   /source_dset
               }
    Storage:   2880 logical bytes, 0 allocated bytes
    Type:      32-bit little-endian integer
