:orphan:
# PetscFileMode
Access mode for a file. 
## Synopsis
```
typedef enum {
  FILE_MODE_UNDEFINED = -1,
  FILE_MODE_READ      = 0,
  FILE_MODE_WRITE,
  FILE_MODE_APPEND,
  FILE_MODE_UPDATE,
  FILE_MODE_APPEND_UPDATE
} PetscFileMode;
```

## Values

- ***`FILE_MODE_UNDEFINED` -*** initial invalid value
- ***`FILE_MODE_READ` -*** open a file at its beginning for reading
- ***`FILE_MODE_WRITE` -*** open a file at its beginning for writing (will create if the file does not exist)
- ***`FILE_MODE_APPEND` -*** open a file at end for writing
- ***`FILE_MODE_UPDATE` -*** open a file for updating, meaning for reading and writing
- ***`FILE_MODE_APPEND_UPDATE` -*** open a file for updating, meaning for reading and writing, at the end





## See Also
 `PetscViewerFileSetMode()`

## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscsystypes.h.html#PetscFileMode">include/petscsystypes.h</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/plex/tutorials/ex5.c.html">src/dm/impls/plex/tutorials/ex5.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/stag/tutorials/ex4.c.html">src/dm/impls/stag/tutorials/ex4.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/impls/stag/tutorials/ex6.c.html">src/dm/impls/stag/tutorials/ex6.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/tutorials/ex1.c.html">src/dm/tutorials/ex1.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/tutorials/ex10.c.html">src/dm/tutorials/ex10.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/tutorials/ex15.c.html">src/dm/tutorials/ex15.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/tutorials/ex20.c.html">src/dm/tutorials/ex20.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/tutorials/ex21.c.html">src/dm/tutorials/ex21.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/tutorials/ex7.c.html">src/dm/tutorials/ex7.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/tutorials/ex9.c.html">src/dm/tutorials/ex9.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex10.c.html">src/ksp/ksp/tutorials/ex10.c</A><BR>


---
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