# PetscBagSetOptionsPrefix
Sets the prefix used for searching for all `PetscBag` items in the options database. 
## Synopsis
```
#include "petscbag.h"   
PetscErrorCode PetscBagSetOptionsPrefix(PetscBag bag, const char pre[])
```
Logically collective




## Input Parameters

- ***bag -*** the bag of values
- ***prefix -*** the prefix to prepend all Bag item names with.


NOTES: Must be called prior to registering any of the bag items.


## See Also
 `PetscBag`, `PetscBagRegisterReal()`, `PetscBagRegisterInt()`, `PetscBagRegisterBool()`, `PetscBagRegisterScalar()`
`PetscBagSetFromOptions()`, `PetscBagCreate()`, `PetscBagDestroy()`, `PetscBagRegisterEnum()`

## Level
Intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/classes/bag/bag.c.html#PetscBagSetOptionsPrefix">src/sys/classes/bag/bag.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/tutorials/ex5.c.html">src/sys/tutorials/ex5.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/tutorials/ex5f90.F90.html">src/sys/tutorials/ex5f90.F90.html</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/sys/classes/bag/bag.c)


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