text: /* -*- Mode: C; c-basic-offset:4 ; -*- */
  /*
   *  (C) 2001 by Argonne National Laboratory.
   *      See COPYRIGHT in top-level directory.
   */
  #include "mpi.h"
  #include <stdlib.h>
  #include <string.h>
  #include <stdio.h>
  
  /* tests various miscellaneous functions. */
  #define VERBOSE 0
  
  static void handle_error(int errcode, const char *str)
  {
  	char msg[MPI_MAX_ERROR_STRING];
  	int resultlen;
  	MPI_Error_string(errcode, msg, &resultlen);
  	fprintf(stderr, "%s: %s\n", str, msg);
  }
  
  int main(int argc, char **argv)
  {
      int buf[1024], amode, flag, mynod, len, i;
      int errs = 0, toterrs;
      MPI_File fh;
      MPI_Status status;
      MPI_Datatype newtype;
      MPI_Offset disp, offset;
      MPI_Group group;
      MPI_Datatype etype, filetype;
      char datarep[25], *filename;
      int errcode=0;
  
      MPI_Init(&argc,&argv);
      MPI_Comm_rank(MPI_COMM_WORLD, &mynod);
  
  /* process 0 takes the file name as a command-line argument and
     broadcasts it to other processes */
      if (!mynod) {
  	i = 1;
  	while ((i < argc) && strcmp("-fname", *argv)) {
  	    i++;
  	    argv++;
  	}
  	if (i >= argc) {
  	    fprintf(stderr, "\n*#  Usage: misc -fname filename\n\n");
  	    MPI_Abort(MPI_COMM_WORLD, 1);
  	}
  	argv++;
  	len = strlen(*argv);
  	filename = (char *) malloc(len+1);
  	strcpy(filename, *argv);
  	MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD);
  	MPI_Bcast(filename, len+1, MPI_CHAR, 0, MPI_COMM_WORLD);
      }
      else {
  	MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD);
  	filename = (char *) malloc(len+1);
  	MPI_Bcast(filename, len+1, MPI_CHAR, 0, MPI_COMM_WORLD);
      }
  
  
      errcode = MPI_File_open(MPI_COMM_WORLD, filename,
  		    MPI_MODE_CREATE | MPI_MODE_RDWR, MPI_INFO_NULL, &fh);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_open");
      }
  
      errcode = MPI_File_write(fh, buf, 1024, MPI_INT, &status);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_write");
      }
  
      errcode = MPI_File_sync(fh);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_sync");
      }
  
      errcode = MPI_File_get_amode(fh, &amode);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_amode");
      }
  #if VERBOSE
      if (!mynod) fprintf(stderr, "testing MPI_File_get_amode\n");
  #endif
      if (amode != (MPI_MODE_CREATE | MPI_MODE_RDWR)) {
  	errs++;
  	fprintf(stderr, "amode is %d, should be %d\n\n",
  		amode, MPI_MODE_CREATE | MPI_MODE_RDWR);
      }
  
      errcode = MPI_File_get_atomicity(fh, &flag);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_atomicity");
      }
      if (flag) {
  	errs++;
  	fprintf(stderr, "atomicity is %d, should be 0\n", flag);
      }
  #if VERBOSE
      if (!mynod) fprintf(stderr, "setting atomic mode\n");
  #endif
      errcode = MPI_File_set_atomicity(fh, 1);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_set_atomicity");
      }
      errcode = MPI_File_get_atomicity(fh, &flag);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_atomicity");
      }
      if (!flag) {
  	errs++;
  	fprintf(stderr, "atomicity is %d, should be 1\n", flag);
      }
      errcode = MPI_File_set_atomicity(fh, 0);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_set_atomicity");
      }
  #if VERBOSE
      if (!mynod) fprintf(stderr, "reverting back to nonatomic mode\n");
  #endif
  
      MPI_Type_vector(10, 10, 20, MPI_INT, &newtype);
      MPI_Type_commit(&newtype);
  
      errcode = MPI_File_set_view(fh, 1000, MPI_INT, newtype, "native", MPI_INFO_NULL);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_set_view");
      }
  #if VERBOSE
      if (!mynod) fprintf(stderr, "testing MPI_File_get_view\n");
  #endif
      errcode = MPI_File_get_view(fh, &disp, &etype, &filetype, datarep);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_view");
      }
      if ((disp != 1000) || strcmp(datarep, "native")) {
  	errs++;
  	fprintf(stderr, "disp = %lld, datarep = %s, should be 1000, native\n\n", disp, datarep);
      }
  #if VERBOSE
      if (!mynod) fprintf(stderr, "testing MPI_File_get_byte_offset\n");
  #endif
      errcode = MPI_File_get_byte_offset(fh, 10, &disp);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_byte_offset");
      }
      if (disp != (1000+20*sizeof(int))) {
  	errs++;
  	fprintf(stderr, "byte offset = %lld, should be %d\n\n",
  		disp, (int) (1000+20*sizeof(int)));
      }
  
      errcode = MPI_File_get_group(fh, &group);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_group");
      }
  
  #if VERBOSE
      if (!mynod) fprintf(stderr, "testing MPI_File_set_size\n");
  #endif
      errcode = MPI_File_set_size(fh, 1000+15*sizeof(int));
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_set_size");
      }
      MPI_Barrier(MPI_COMM_WORLD);
      errcode = MPI_File_sync(fh);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_sync");
      }
      errcode = MPI_File_get_size(fh, &disp);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_size");
      }
      if (disp != 1000+15*sizeof(int)) {
  	errs++;
  	fprintf(stderr, "file size = %lld, should be %d\n\n",
  		disp, (int) (1000+15*sizeof(int)));
      }
  
  #if VERBOSE
      if (!mynod) fprintf(stderr, "seeking to eof and testing MPI_File_get_position\n");
  #endif
      errcode = MPI_File_seek(fh, 0, MPI_SEEK_END);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_seek");
      }
      errcode = MPI_File_get_position(fh, &disp);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_position");
      }
      if (disp != 10) {
  	errs++;
  	fprintf(stderr, "file pointer posn = %lld, should be 10\n\n", disp);
      }
  
  #if VERBOSE
      if (!mynod) fprintf(stderr, "testing MPI_File_get_byte_offset\n");
  #endif
      errcode = MPI_File_get_byte_offset(fh, disp, &offset);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_byte_offset");
      }
      if (offset != (1000+20*sizeof(int))) {
  	errs++;
  	fprintf(stderr, "byte offset = %lld, should be %d\n\n",
  		offset, (int) (1000+20*sizeof(int)));
      }
      MPI_Barrier(MPI_COMM_WORLD);
  
  #if VERBOSE
      if (!mynod) fprintf(stderr, "testing MPI_File_seek with MPI_SEEK_CUR\n");
  #endif
      errcode = MPI_File_seek(fh, -10, MPI_SEEK_CUR);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_seek");
      }
      errcode = MPI_File_get_position(fh, &disp);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_position");
      }
      errcode = MPI_File_get_byte_offset(fh, disp, &offset);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_get_byte_offset");
      }
      if (offset != 1000) {
  	errs++;
  	fprintf(stderr, "file pointer posn in bytes = %lld, should be 1000\n\n", offset);
      }
  
  #if VERBOSE
      if (!mynod) fprintf(stderr, "preallocating disk space up to 8192 bytes\n");
  #endif
      errcode = MPI_File_preallocate(fh, 8192);
      if (errcode != MPI_SUCCESS) {
  	    handle_error(errcode, "MPI_File_Preallocate");
      }
  
  #if VERBOSE
      if (!mynod) fprintf(stderr, "closing the file and deleting it\n");
  #endif
      MPI_File_close(&fh);
  
      MPI_Barrier(MPI_COMM_WORLD);
      if (!mynod) MPI_File_delete(filename, MPI_INFO_NULL);
  
      MPI_Allreduce( &errs, &toterrs, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD );
      if (mynod == 0) {
  	if( toterrs > 0) {
  	    fprintf( stderr, "Found %d errors\n", toterrs );
  	}
  	else {
  	    fprintf( stdout, " No Errors\n" );
  	}
      }
      MPI_Type_free(&newtype);
      MPI_Type_free(&filetype);
      MPI_Group_free(&group);
      free(filename);
      MPI_Finalize();
      return 0;
  }
  