/* *  Test for null proc handling with non-blocking routines */#include <stdio.h>#include "mpi.h"#if defined(NEEDS_STDLIB_PROTOTYPES)#include "protofix.h"#endifint main( int argc, char *argv[] ){   int             a[4];   int             i, nproc;   int             rank, right, left;   MPI_Status      status;   MPI_Request     req[4];   int             index, it, count, errcnt = 0;   /* start up */   MPI_Init(&argc, &argv);   MPI_Comm_size(MPI_COMM_WORLD, &nproc);   MPI_Comm_rank(MPI_COMM_WORLD, &rank);   /* set up processor chain (Apps should use Cart_create/shift) */   left = (rank == 0) ? MPI_PROC_NULL : rank - 1;   right = (rank == nproc - 1) ? MPI_PROC_NULL : rank + 1;   /* initialize local matrix */   /* globally: a[i] = i, i = 1 .. 2*nproc */   /* locally : a[i] = 2*rank+i, i=1,2 */   a[0] = -1;   a[1] = 2*rank + 1;    a[2] = 2*rank + 2;    a[3] = -1;   /* start all receives and sends */   MPI_Irecv(&a[0], 1, MPI_INT, left,  1, MPI_COMM_WORLD, &req[0]);   MPI_Irecv(&a[3], 1, MPI_INT, right, 0, MPI_COMM_WORLD, &req[3]);   MPI_Isend(&a[1], 1, MPI_INT, left, 0, MPI_COMM_WORLD, &req[1]);   MPI_Isend(&a[2], 1, MPI_INT, right,  1, MPI_COMM_WORLD, &req[2]);   for (it=0; it<4; it++) {       status.MPI_SOURCE = nproc;       status.MPI_TAG = nproc;       MPI_Waitany( 4, req, &index, &status );       if (index == 0 && left == MPI_PROC_NULL) {	   if (status.MPI_TAG != MPI_ANY_TAG ||	       status.MPI_SOURCE != MPI_PROC_NULL) {	       errcnt ++;	       fprintf( stderr, "Incorrect null status for left\n" );	   }	   MPI_Get_count( &status, MPI_INT, &count );	   if (count != 0) {	       errcnt ++;	       fprintf( stderr, "Incorrect null status for left (count)\n" );	   }       }       else if (index == 3 && right == MPI_PROC_NULL) {	   if (status.MPI_TAG != MPI_ANY_TAG ||	       status.MPI_SOURCE != MPI_PROC_NULL) {	       errcnt ++;	       fprintf( stderr, "Incorrect null status for right\n" );	   }	   MPI_Get_count( &status, MPI_INT, &count );	   if (count != 0) {	       errcnt ++;	       fprintf( stderr, "Incorrect null status for right (count)\n" );	   }       }   }      /* Test results */   if (left == MPI_PROC_NULL) {       if (a[0] != -1) {	   fprintf( stderr, "Expected -1, found %d in left partner\n", a[0] );	   errcnt ++;       }   }   else {       if (a[0] != 2 * left + 2) {	   fprintf( stderr, "Expected %d, found %d in left partner\n", 		    2 * left + 2, a[0] );	   errcnt ++;       }   }   if (right == MPI_PROC_NULL) {       if (a[3] != -1) {	   fprintf( stderr, "Expected -1, found %d in right partner\n", a[3] );	   errcnt ++;       }   }   else {       if (a[3] != 2 * right + 1) {	   fprintf( stderr, "Expected %d, found %d in right partner\n", 		    2 * right + 1, a[3] );	   errcnt ++;       }   }      i = errcnt;   MPI_Allreduce( &i, &errcnt, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD );   if (rank == 0) {       if (errcnt > 0) {	   printf( "Found %d errors in the run \n", errcnt );       }       else	   printf( "No errors in handling MPI_PROC_NULL\n" );   }      /* clean up */   MPI_Finalize();   return 0;}