# MPI_Aint_diff

Returns the difference between addr1 and addr2

## Synopsis

    #ifdef ENABLE_QMPI
    #ifndef MPICH_MPI_FROM_PMPI
    MPI_Aint QMPI_Aint_diff(QMPI_Context context, int tool_id, MPI_Aint addr1,
                            MPI_Aint addr2) MPICH_API_PUBLIC

## Input Parameters

addr1
  minuend address (integer)
addr2
  subtrahend address (integer)

## Notes

MPI_Aint_diff produces a new MPI_Aint value that is equivalent to the difference between addr1 and addr2 arguments, where addr1 and addr2 represent addresses returned by calls to MPI_GET_ADDRESS. The resulting address is valid only at the process that generated addr1 and addr2, and addr1 and addr2 must correspond to locations in the same object in the same process. The difference is calculated in a manner that results the signed difference from addr1 to addr2, as if the process that originally produced the addresses had called

        (char *) addr1 - (char *) addr2

on the addresses initially passed to MPI_GET_ADDRESS.

## See Also

MPI_Aint_add