PetscOptionsGetString#
Gets the string value for a particular option in the database.
Synopsis#
#include "petscsys.h"   
PetscErrorCode PetscOptionsGetString(PetscOptions options, const char pre[], const char name[], char string[], size_t len, PetscBool *set)
Not Collective
Input Parameters#
- options - options database, use - NULLfor default global database
- pre - string to prepend to name or - NULL
- name - the option one is seeking 
- len - maximum length of the string including null termination 
Output Parameters#
- string - location to copy string 
- set - - PETSC_TRUEif found, else- PETSC_FALSE
Note#
if the option is given but no string is provided then an empty string is returned and set is given the value of PETSC_TRUE
If the user does not use the option then string is not changed. Thus
you should ALWAYS initialize string if you access it without first checking that the set flag is true.
Fortran Notes#
The Fortran interface is slightly different from the C/C++ interface (len is not used). Sample usage in Fortran follows
      character *20    string
      PetscErrorCode   ierr
      PetscBool        set
      call PetscOptionsGetString(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER,'-s',string,set,ierr)
See Also#
PetscOptionsGetInt(), PetscOptionsGetReal(),
PetscOptionsHasName(), PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool(),
PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHeadBegin(),
PetscOptionsStringArray(), PetscOptionsRealArray(), PetscOptionsScalar(),
PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
PetscOptionsFList(), PetscOptionsEList()
Level#
beginner
Location#
Examples#
src/ksp/ksp/tutorials/ex43.c
src/ksp/ksp/tutorials/ex77.c
src/ksp/ksp/tutorials/ex75.c
src/dm/impls/stag/tutorials/ex4.c
src/ksp/ksp/tutorials/ex27.c
src/ksp/ksp/tutorials/ex72.c
src/ksp/ksp/tutorials/ex77f.F90
src/dm/label/tutorials/ex1f90.F90
src/ksp/ksp/tutorials/ex75f.F90
src/ksp/ksp/tutorials/ex76f.F90
Index of all Sys routines
Table of Contents for all manual pages
Index of all manual pages