7 /* Test reading and writing zero bytes (set status correctly) */
9 int main( int argc, char *argv[] )
21 MPI_Init( &argc, &argv );
23 comm = MPI_COMM_WORLD;
24 MPI_File_open( comm, (char*)"/scratch/testfile", MPI_MODE_RDWR | MPI_MODE_CREATE | MPI_MODE_DELETE_ON_CLOSE, MPI_INFO_NULL, &fh );
25 MPI_Comm_size( comm, &size );
26 MPI_Comm_rank( comm, &rank );
27 buf = (int *)malloc( size * sizeof(int) );
31 MPI_File_write_at( fh, sizeof(int)*rank, buf, 1, MPI_INT, &status );
32 MPI_Get_count( &status, MPI_INT, &count );
35 fprintf( stderr, "Wrong count (%d) on write_at\n", count );fflush(stderr);
38 /* Read nothing (check status) */
39 memset( &status, 0xff, sizeof(MPI_Status) );
40 MPI_File_read_at( fh, sizeof(int)*rank, buf, 0, MPI_INT, &status );
41 MPI_Get_count( &status, MPI_INT, &count );
44 fprintf( stderr, "Count not zero (%d) on read\n", count );fflush(stderr);
47 /* Write nothing (check status) */
48 memset( &status, 0xff, sizeof(MPI_Status) );
49 MPI_File_write_at( fh, sizeof(int)*rank, buf, 0, MPI_INT, &status );
52 fprintf( stderr, "Count not zero (%d) on write\n", count );fflush(stderr);
57 for (i=0; i<size; i++) buf[i] = -1;
58 MPI_File_read_at( fh, sizeof(int)*rank, buf, 1, MPI_INT, &status );
59 // if (buf[0] != rank) {
61 // fprintf( stderr, "%d: buf = %d\n", rank, buf[0] );fflush(stderr);
65 MPI_File_close( &fh );