#include <stdio.h>
#include <stdlib.h>
#include <unistd.h> /* unlink() */
#include <mpi.h>

int main(int argc, char **argv) {
    int      err;
    MPI_File fh;

    MPI_Init(&argc, &argv);
    if (argc != 2) {
        printf("Usage: %s filename\n",argv[0]);
        MPI_Finalize();
        return 1;
    }
    unlink(argv[1]); /* delete the file and ignore the error */

    err = MPI_File_open(MPI_COMM_WORLD, argv[1], MPI_MODE_RDONLY,
                        MPI_INFO_NULL, &fh);
    if (err != MPI_SUCCESS) {
        char err_string[MPI_MAX_ERROR_STRING+1];
        int  err_len, errorclass;
        MPI_Error_string(err, err_string, &err_len);
        MPI_Error_class(err, &errorclass);
        printf("non-exiting file \"%s\"\n",argv[1]);
        printf("MPI error string: %s\n",err_string);
        if (errorclass == MPI_ERR_NO_SUCH_FILE)
            printf("Error class = MPI_ERR_NO_SUCH_FILE\n");
        else if (errorclass == MPI_ERR_IO)
            printf("Error class = MPI_ERR_IO\n");
        else
            printf("Error class = %d\n",errorclass);
    }
    else {
        MPI_File_close(&fh);
        printf("Open non-existing file %s unexpected succeeded\n",argv[1]);
    }

    MPI_Finalize();
    return 0;
}