io6.c
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	/* parallel MPI read with arbitrary number of processes*/
	#include "mpi.h"
	#include <malloc.h>
	#include <stdio.h>
	int main(int argc, char *argv[])
	{
	int myrank, numprocs, bufsize, *buf, count;
	MPI_File thefile;
	MPI_Status status;
	MPI_Offset filesize;

	MPI_Init(&argc, &argv);
	MPI_Comm_rank(MPI_COMM_WORLD, &myrank);
	MPI_Comm_size(MPI_COMM_WORLD, &numprocs);
	MPI_File_open(MPI_COMM_WORLD, "testfile", MPI_MODE_RDONLY,
	MPI_INFO_NULL, &thefile);
	MPI_File_get_size(thefile, &filesize); /* in bytes */
	filesize = filesize / sizeof(int); /* in number of ints */
	bufsize = filesize / numprocs + 1; /* local number to read */
	buf = (int ) malloc (bufsize sizeof(int));
	MPI_File_set_view(thefile, myrank * bufsize * sizeof(int),
	MPI_INT, MPI_INT, "native", MPI_INFO_NULL);
	MPI_File_read(thefile, buf, bufsize, MPI_INT, &status);
	MPI_Get_count(&status, MPI_INT, &count);
	printf("process %d read %d ints\n", myrank, count);
	MPI_File_close(&thefile);
	MPI_Finalize();
	return 0;
	}