#include <stdlib.h>
#include <mpi.h> 
 
#define FILESIZE      4096
#define INTS_PER_BLK    16 
 
int main(int argc, char **argv) 
{ 
    int *mydata, myrank, numprocs, numints;
    MPI_File fh; 
    MPI_Datatype filetype; 
 
    MPI_Init(&argc,&argv); 
    MPI_Comm_rank(MPI_COMM_WORLD, &myrank); 
    MPI_Comm_size(MPI_COMM_WORLD, &numprocs); 
 
    mydata = (int *) malloc(FILESIZE/numprocs); 
    numints = FILESIZE/(sizeof(int)*numprocs); 
 
    MPI_File_open(MPI_COMM_WORLD, "/work/datafile", MPI_MODE_RDONLY, 
		MPI_INFO_NULL, &fh); 
 
    MPI_Type_vector(numints/INTS_PER_BLK, INTS_PER_BLK,  
                    INTS_PER_BLK*numprocs, MPI_INT, &filetype); 
    MPI_Type_commit(&filetype); 
    MPI_File_set_view(fh, sizeof(int)*INTS_PER_BLK*myrank, MPI_INT,
		 filetype, "native", MPI_INFO_NULL); 
 
    MPI_File_read_all(fh, mydata, numints, MPI_INT, MPI_STATUS_IGNORE);

    MPI_File_close(&fh); 
    MPI_Type_free(&filetype); 
    free(mydata); 
    MPI_Finalize(); 

    return 0;  
}