Hello, I was wondering if MPI allows changing the file view after issuing a non-blocking I/O operation. Here is a snipet of what I want to achieve: MPI_Offset disp1,disp2; MPI_Request rqst1,rqst2; // Write first section MPI_File_set_view(fhandle,disp1,MPI_DOUBLE,MPI_DOUBLE, const_cast<char*>("native"), MPI_INFO_NULL ); MPI_File_iwrite_at(fhandle,0,array1,N,MPI_DOUBLE, &rqst1 ); // Write second section MPI_File_set_view(fhandle,disp1,MPI_DOUBLE,MPI_DOUBLE, const_cast<char*>("native"), MPI_INFO_NULL ); MPI_File_iwrite_at(fhandle,0,array2,N,MPI_DOUBLE,&rqst2); MPI_Wait(rqst1); MPI_Wait(rqst2); My concern is that the second MPI_File_set_view will interfere with previously issued non-blocking write. Any thoughts or suggestions? Thank you very much for all your time & help. Best, George