xref: /petsc/src/sys/tutorials/ex16.c (revision dfd57a172ac9fa6c7b5fe6de6ab5df85cefc2996)
1c4762a1bSJed Brown 
2c4762a1bSJed Brown static char help[] = "Tests calling PetscOptionsSetValue() before PetscInitialize()\n\n";
3c4762a1bSJed Brown 
4c4762a1bSJed Brown /*T
5c4762a1bSJed Brown    Concepts: introduction to PETSc;
6c4762a1bSJed Brown    Concepts: printing^in parallel
7c4762a1bSJed Brown    Processors: n
8c4762a1bSJed Brown T*/
9c4762a1bSJed Brown 
10c4762a1bSJed Brown #include <petscsys.h>
11c4762a1bSJed Brown int main(int argc,char **argv)
12c4762a1bSJed Brown {
13c4762a1bSJed Brown   PetscErrorCode ierr;
14c4762a1bSJed Brown   PetscMPIInt    rank,size;
15c4762a1bSJed Brown 
16c4762a1bSJed Brown   /*
17c4762a1bSJed Brown     Every PETSc routine should begin with the PetscInitialize() routine.
18c4762a1bSJed Brown     argc, argv - These command line arguments are taken to extract the options
19c4762a1bSJed Brown                  supplied to PETSc and options supplied to MPI.
20c4762a1bSJed Brown     help       - When PETSc executable is invoked with the option -help,
21c4762a1bSJed Brown                  it prints the various options that can be applied at
22c4762a1bSJed Brown                  runtime.  The user can use the "help" variable place
23c4762a1bSJed Brown                  additional help messages in this printout.
24c4762a1bSJed Brown 
25c4762a1bSJed Brown     Since when PetscInitialize() returns with an error the PETSc data structures
26c4762a1bSJed Brown     may not be set up hence we cannot call CHKERRQ() hence directly return the error code.
27c4762a1bSJed Brown 
28c4762a1bSJed Brown     Since PetscOptionsSetValue() is called before the PetscInitialize() we cannot call
29c4762a1bSJed Brown     CHKERRQ() on the error code and just return it directly.
30c4762a1bSJed Brown   */
31c4762a1bSJed Brown   ierr = PetscOptionsSetValue(NULL,"-no_signal_handler","true");if (ierr) return ierr;
32c4762a1bSJed Brown   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
33ffc4695bSBarry Smith   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRMPI(ierr);
34ffc4695bSBarry Smith   ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRMPI(ierr);
35c4762a1bSJed Brown   ierr = PetscPrintf(PETSC_COMM_WORLD,"Number of processors = %d, rank = %d\n",size,rank);CHKERRQ(ierr);
36c4762a1bSJed Brown   ierr = PetscFinalize();
37c4762a1bSJed Brown   return ierr;
38c4762a1bSJed Brown }
39c4762a1bSJed Brown 
40c4762a1bSJed Brown /*TEST
41c4762a1bSJed Brown 
42c4762a1bSJed Brown    test:
43*dfd57a17SPierre Jolivet       requires: defined(PETSC_USE_LOG)
44c4762a1bSJed Brown       nsize: 2
45c4762a1bSJed Brown       args: -options_view -get_total_flops
46362febeeSStefano Zampini       filter: egrep -v "(cuda_initialize|malloc|display|nox|Total flops|saws_port_auto_select|vecscatter_mpi1|options_left|error_output_stdout|check_pointer_intensity|use_gpu_aware_mpi|checkstack)"
47c4762a1bSJed Brown 
48c4762a1bSJed Brown TEST*/
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