# PetscViewerHDF5ReadObjectAttribute
Read an attribute from the dataset matching the given `PetscObject` by name 
## Synopsis
```
#include "petscviewerhdf5.h" 
PetscErrorCode PetscViewerHDF5ReadObjectAttribute(PetscViewer viewer, PetscObject obj, const char name[], PetscDataType datatype, void *defaultValue, void *value)
```
Collective


## Input Parameters

- ***viewer   -*** The `PETSCVIEWERHDF5` viewer
- ***obj      -*** The object whose name is used to lookup the parent dataset, relative to the current group.
- ***name     -*** The attribute name
- ***datatype -*** The attribute type



## Output Parameter

- ***value    -*** The attribute value



## Note
This fails if current_group/object_name doesn't resolve to a dataset (the path doesn't exist or is not a dataset).
You might want to check first if it does using `PetscViewerHDF5HasObject()`.




## See Also
 `PETSCVIEWERHDF5`, `PetscViewerHDF5Open()`, `PetscViewerHDF5ReadAttribute()` `PetscViewerHDF5WriteObjectAttribute()`, `PetscViewerHDF5HasObjectAttribute()`, `PetscViewerHDF5PushGroup()`, `PetscViewerHDF5PopGroup()`, `PetscViewerHDF5GetGroup()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/classes/viewer/impls/hdf5/hdf5v.c.html#PetscViewerHDF5ReadObjectAttribute">src/sys/classes/viewer/impls/hdf5/hdf5v.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/sys/classes/viewer/impls/hdf5/hdf5v.c)


[Index of all Viewer routines](index.md)  
[Table of Contents for all manual pages](/docs/manualpages/index.md)  
[Index of all manual pages](/docs/manualpages/singleindex.md)  
