# Module H5O

Module for HDF5 “`H5O`” functions.

## Functional API

h5py.h5o.open(ObjectID loc, STRING name, PropID lapl=None) → ObjectID

  Open a group, dataset, or named datatype attached to an existing group.

h5py.h5o.link(ObjectID obj, GroupID loc, STRING name, PropID lcpl=None, PropID lapl=None)

  Create a new hard link to an object. Useful for objects created with h5g.create_anon() or h5d.create_anon().

h5py.h5o.copy(ObjectID src_loc, STRING src_name, GroupID dst_loc, STRING dst_name, PropID copypl=None, PropID lcpl=None)

  Copy a group, dataset or named datatype from one location to another. The source and destination need not be in the same file.

  The default behavior is a recursive copy of the object and all objects below it. This behavior is modified via the “copypl” property list.

h5py.h5o.set_comment(ObjectID loc, STRING comment, **kwds)

  Set the comment for any-file resident object. Keywords:

  STRING obj_name (“.”)

    Set comment on this group member instead

  PropID lapl (None)

    Link access property list

h5py.h5o.get_comment(ObjectID loc, STRING comment, **kwds)

  Get the comment for any-file resident object. Keywords:

  STRING obj_name (“.”)

    Set comment on this group member instead

  PropID lapl (None)

    Link access property list

h5py.h5o.visit(ObjectID loc, CALLABLE func, **kwds) → <Return value from func>

  Iterate a function or callable object over all objects below the specified one. Your callable should conform to the signature:

      func(STRING name) => Result

  or if the keyword argument “info” is True:

      func(STRING name, ObjInfo info) => Result

  Returning None continues iteration; returning anything else aborts iteration and returns that value. Keywords:

  BOOL info (False)

    Callback is func(STRING, Objinfo)

  STRING obj_name (“.”)

    Visit a subgroup of “loc” instead

  PropLAID lapl (None)

    Control how “obj_name” is interpreted

  INT idx_type (`h5.INDEX_NAME`)

    What indexing strategy to use

  INT order (`h5.ITER_INC`)

    Order in which iteration occurs

  Compatibility note: No callback is executed for the starting path (“.”), as some versions of HDF5 don’t correctly handle a return value for this case. This differs from the behavior of the native H5Ovisit, which provides a literal “.” as the first value.

h5py.h5o.get_info(ObjectID loc, STRING name=, INT index=, **kwds) → ObjInfo

  Get information describing an object in an HDF5 file. Provide the object itself, or the containing group and exactly one of “name” or “index”.

  STRING obj_name (“.”)

    When “index” is specified, look in this subgroup instead. Otherwise ignored.

  PropID lapl (None)

    Link access property list

  INT index_type (`h5.INDEX_NAME`)

  INT order (`h5.ITER_INC`)

## Info classes

class h5py.h5o.ObjInfo

  Represents the H5O_info_t structure

## Module constants

### Object types

h5py.h5o.TYPE_GROUP

h5py.h5o.TYPE_DATASET

h5py.h5o.TYPE_NAMED_DATATYPE

### Copy flags

h5py.h5o.COPY_SHALLOW_HIERARCHY_FLAG

  Copy only immediate members of a group.

h5py.h5o.COPY_EXPAND_SOFT_LINK_FLAG

  Expand soft links into new objects.

h5py.h5o.COPY_EXPAND_EXT_LINK_FLAG

  Expand external link into new objects.

h5py.h5o.COPY_EXPAND_REFERENCE_FLAG

  Copy objects that are pointed to by references.

h5py.h5o.COPY_WITHOUT_ATTR_FLAG

  Copy object without copying attributes.