MPIIO_INDEP_OPENS

In "Darshan-util installation and usage", Table 2. MPI-IO module, counter MPIIO_INDEP_OPENS is "Count of non-collective MPI opens". My understanding of MPI file open is the function is always collective, for the processes in the MPI communicator passed to the MPI file open call. What information is this counter trying to collect? Number of calls to MPI_File_open when MPI_COMM_SELF is used?