:orphan:
# DMAppendOptionsPrefix
Appends an additional string to an already existing prefix used for searching for `DM` options in the options database. 
## Synopsis
```
#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMAppendOptionsPrefix(DM dm, const char prefix[])
```
Logically Collective


## Input Parameters

- ***dm -*** the `DM` context
- ***prefix -*** the string to append to the current prefix





## Note
If the `DM` does not currently have an options prefix then this value is used alone as the prefix as if `DMSetOptionsPrefix()` had been called.
A hyphen (-) must NOT be given at the beginning of the prefix name.
The first character of all runtime options is AUTOMATICALLY the hyphen.


## See Also
 [](ch_dmbase), `DM`, `DMSetOptionsPrefix()`, `DMGetOptionsPrefix()`, `PetscObjectAppendOptionsPrefix()`, `DMSetFromOptions()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/interface/dm.c.html#DMAppendOptionsPrefix">src/dm/interface/dm.c</A>


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