mirror of
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ca33a5498c
Purpose:
To facilitate finding functions, particularly in long Reference Manual
sections.
Solution:
Added alphabetized function listings. (NOTE: Aside from the H5I and H5Z
sections, this is not necessarily the final implementation; there will
likely be another revision in the presentation of this listing before it
is released.)
Platforms tested:
Safari, IE 5
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<html>
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<head><title>
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HDF5/H5A API Specification
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</title>
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<body bgcolor="#FFFFFF">
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<center>
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<table border=0 width=98%>
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<tr><td valign=top align=left>
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<a href="index.html">HDF5 documents and links</a> <br>
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<a href="H5.intro.html">Introduction to HDF5</a> <br>
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<a href="H5.user.html">HDF5 User Guide</a> <br>
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<!--
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<a href="Glossary.html">Glossary</a><br>
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-->
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</td>
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<td valign=top align=right>
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And in this document, the
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<a href="RM_H5Front.html">HDF5 Reference Manual</a>
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<br>
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<a href="RM_H5.html">H5</a>
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<a href="RM_H5A.html">H5A</a>
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<a href="RM_H5D.html">H5D</a>
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<a href="RM_H5E.html">H5E</a>
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<a href="RM_H5F.html">H5F</a>
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<a href="RM_H5G.html">H5G</a>
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<a href="RM_H5I.html">H5I</a>
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<a href="RM_H5P.html">H5P</a>
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<br>
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<a href="RM_H5R.html">H5R</a>
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<a href="RM_H5S.html">H5S</a>
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<a href="RM_H5T.html">H5T</a>
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<a href="RM_H5Z.html">H5Z</a>
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<a href="Tools.html">Tools</a>
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<a href="PredefDTypes.html">Datatypes</a>
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</td></tr>
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</table>
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</center>
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<hr>
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<!-- #EndLibraryItem --><center>
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<h1>H5A: Attribute Interface</h1>
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</center>
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<h2>Attribute API Functions</h2>
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These functions create and manipulate attributes
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and information about attributes.
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<p>
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<strong>The C Interfaces:</strong>
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<table border=0>
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<tr><td valign=top>
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<ul>
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<li><a href="#Annot-Create">H5Acreate</a>
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<li><a href="#Annot-Write">H5Awrite</a>
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<li><a href="#Annot-Read">H5Aread</a>
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<li><a href="#Annot-Close">H5Aclose</a>
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</ul>
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</td><td> </td><td valign=top>
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<ul>
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<li><a href="#Annot-GetName">H5Aget_name</a>
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<li><a href="#Annot-OpenName">H5Aopen_name</a>
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<li><a href="#Annot-OpenIdx">H5Aopen_idx</a>
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<li><a href="#Annot-GetSpace">H5Aget_space</a>
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</ul>
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</td><td> </td><td valign=top>
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<ul>
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<li><a href="#Annot-GetType">H5Aget_type</a>
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<li><a href="#Annot-NumAttrs">H5Aget_num_attrs</a>
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<li><a href="#Annot-Iterate">H5Aiterate</a>
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<li><a href="#Annot-Delete">H5Adelete</a>
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</ul>
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</td></tr>
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</table>
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<br>
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<i>Alphabetical Listing</i>
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<table border="0">
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<tr>
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<td valign="top">
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<li><a href="#Annot-Close">H5Aclose</a>
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<li><a href="#Annot-Create">H5Acreate</a>
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<li><a href="#Annot-Delete">H5Adelete</a>
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<li><a href="#Annot-GetName">H5Aget_name</a>
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</td>
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<td> </td>
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<td valign="top">
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<li><a href="#Annot-NumAttrs">H5Aget_num_attrs</a>
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<li><a href="#Annot-GetSpace">H5Aget_space</a>
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<li><a href="#Annot-GetType">H5Aget_type</a>
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<li><a href="#Annot-Iterate">H5Aiterate</a>
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</td>
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<td> </td>
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<td valign="top">
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<li><a href="#Annot-OpenIdx">H5Aopen_idx</a>
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<li><a href="#Annot-OpenName">H5Aopen_name</a>
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<li><a href="#Annot-Read">H5Aread</a>
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<li><a href="#Annot-Write">H5Awrite</a>
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</td>
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</tr>
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</table>
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<p>
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<strong>The FORTRAN90 Interfaces:</strong>
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<br>
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<font size=-1>
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<i>In general, each FORTRAN90 subroutine performs exactly the same task
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as the corresponding C function. The links below go to the C function
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descriptions, which serve as general descriptions for both. A button,
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under <strong>Non-C API(s)</strong> at the end of the C function description,
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opens an external browser window displaying the FORTRAN90-specific
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information. You will probably want to adjust the size and location of
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this external window so that both browser windows are visible and to
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facilitate moving easily between them.</i>
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</font>
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<table border=0>
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<tr><td valign=top>
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<ul>
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<li><a href="#Annot-Create">h5acreate_f</a>
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<li><a href="#Annot-Write">h5awrite_f</a>
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<li><a href="#Annot-Read">h5aread_f</a>
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<li><a href="#Annot-Close">h5aclose_f</a>
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</ul>
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</td><td> </td><td valign=top>
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<ul>
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<li><a href="#Annot-GetName">h5aget_name_f</a>
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<li><a href="#Annot-OpenName">h5aopen_name_f</a>
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<li><a href="#Annot-OpenIdx">h5aopen_idx_f</a>
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<li><a href="#Annot-GetSpace">h5aget_space_f</a>
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</ul>
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</td><td> </td><td valign=top>
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<ul>
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<li><a href="#Annot-GetType">h5aget_type_f</a>
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<li><a href="#Annot-NumAttrs">h5aget_num_attrs_f</a>
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<!--<li><a href="#Annot-Iterate">h5aiterate_f</a>-->
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<li><a href="#Annot-Delete">h5adelete_f</a>
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</ul>
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</td></tr>
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</table>
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<p>
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The Attribute interface, H5A, is primarily designed to easily allow
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small datasets to be attached to primary datasets as metadata information.
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Additional goals for the H5A interface include keeping storage requirement
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for each attribute to a minimum and easily sharing attributes among
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datasets.
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<p>
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Because attributes are intended to be small objects, large datasets
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intended as additional information for a primary dataset should be
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stored as supplemental datasets in a group with the primary dataset.
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Attributes can then be attached to the group containing everything
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to indicate a particular type of dataset with supplemental datasets
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is located in the group. How small is "small" is not defined by the
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library and is up to the user's interpretation.
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<p>
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See <a href="Attributes.html"><cite>Attributes</cite></a> in the
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<a href="H5.user.html"><cite>HDF5 User's Guide</cite></a> for further information.
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<hr>
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<dl>
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<dt><strong>Name:</strong> <a name="Annot-Create">H5Acreate</a>
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<dt><strong>Signature:</strong>
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<dd><em>hid_t</em> <code>H5Acreate</code>(<em>hid_t</em> <code>loc_id</code>,
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<em>const char *</em><code>name</code>,
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<em>hid_t</em> <code>type_id</code>,
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<em>hid_t</em> <code>space_id</code>,
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<em>hid_t</em> <code>create_plist</code>
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)
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<dt><strong>Purpose:</strong>
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<dd>Creates a dataset as an attribute of another group, dataset,
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or named datatype.
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<dt><strong>Description:</strong>
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<dd><code>H5Acreate</code> creates an attribute named <code>name</code>
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and attached to the object specified with <code>loc_id</code>.
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<code>loc_id</code> is a group, dataset, or named datatype identifier.
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<p>
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The attribute name specified in <code>name</code> must be unique.
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Attempting to create an attribute with the same name as an already
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existing attribute will fail, leaving the pre-existing attribute
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in place. To overwrite an existing attribute with a new attribute
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of the same name, first call <code>H5Adelete</code> then recreate
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the attribute with <code>H5Acreate</code>.
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<p>
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The datatype and dataspace identifiers of the attribute,
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<code>type_id</code> and <code>space_id</code>, respectively,
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are created with the H5T and H5S interfaces, respectively.
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<p>
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Currently only simple dataspaces are allowed for attribute dataspaces.
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<p>
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The attribute creation property list, <code>create_plist</code>,
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is currently unused;
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it may be used in the future for optional attribute properties.
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At this time, <code>H5P_DEFAULT</code> is the only accepted value.
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<p>
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The attribute identifier returned from this function must be released
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with <code>H5Aclose</code> or resource leaks will develop.
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<dt><strong>Parameters:</strong>
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<dl>
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<dt><em>hid_t</em> <code>loc_id</code>
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<dd>IN: Object (dataset, group, or named datatype) to be attached to.
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<dt><em>const char *</em><code>name</code>
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<dd>IN: Name of attribute to create.
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<dt><em>hid_t</em> <code>type_id</code>
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<dd>IN: Identifier of datatype for attribute.
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<dt><em>hid_t</em> <code>space_id</code>
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<dd>IN: Identifier of dataspace for attribute.
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<dt><em>hid_t</em> <code>create_plist</code>
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<dd>IN: Identifier of creation property list. (Currently unused;
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the only accepted value is <code>H5P_DEFAULT</code>.)
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</dl>
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<dt><strong>Returns:</strong>
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<dd>Returns an attribute identifier if successful;
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otherwise returns a negative value.
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<dt><strong>Non-C API(s):</strong>
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<dd><a href="fortran/h5a_FORTRAN.html#h5acreate_f"
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target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
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<!--
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<img src="Graphics/Java.gif">
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<img src="Graphics/C++.gif">
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-->
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</dl>
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<hr>
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<dl>
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<dt><strong>Name:</strong> <a name="Annot-OpenName">H5Aopen_name</a>
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<dt><strong>Signature:</strong>
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<dd><em>hid_t</em> <code>H5Aopen_name</code>(<em>hid_t</em> <code>loc_id</code>,
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<em>const char *</em><code>name</code>
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)
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<dt><strong>Purpose:</strong>
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<dd> Opens an attribute specified by name.
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<dt><strong>Description:</strong>
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<dd><code>H5Aopen_name</code> opens an attribute specified by
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its name, <code>name</code>, which is attached to the
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object specified with <code>loc_id</code>.
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The location object may be either a group, dataset, or
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named datatype, which may have any sort of attribute.
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The attribute identifier returned from this function must
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be released with <code>H5Aclose</code> or resource leaks
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will develop.
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<dt><strong>Parameters:</strong>
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<dl>
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<dt><em>hid_t</em> <code>loc_id</code>
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<dd>IN: Identifier of a group, dataset, or named datatype
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atttribute to be attached to.
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<dt><em>const char *</em><code>name</code>
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<dd>IN: Attribute name.
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</dl>
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<dt><strong>Returns:</strong>
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<dd>Returns attribute identifier if successful;
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otherwise returns a negative value.
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<dt><strong>Non-C API(s):</strong>
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<dd><a href="fortran/h5a_FORTRAN.html#h5aopen_name_f"
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target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
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<!--
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<img src="Graphics/Java.gif">
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<img src="Graphics/C++.gif">
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-->
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</dl>
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<hr>
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<dl>
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<dt><strong>Name:</strong> <a name="Annot-OpenIdx">H5Aopen_idx</a>
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<dt><strong>Signature:</strong>
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<dd><em>hid_t</em> <code>H5Aopen_idx</code>(<em>hid_t</em> <code>loc_id</code>,
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<em>unsigned int</em> <code>idx</code>
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)
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<dt><strong>Purpose:</strong>
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<dd>Opens the attribute specified by its index.
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<dt><strong>Description:</strong>
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<dd><code>H5Aopen_idx</code> opens an attribute which is attached
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to the object specified with <code>loc_id</code>.
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The location object may be either a group, dataset, or
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named datatype, all of which may have any sort of attribute.
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The attribute specified by the index, <code>idx</code>,
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indicates the attribute to access.
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The value of <code>idx</code> is a 0-based, non-negative integer.
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The attribute identifier returned from this function must be
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released with <code>H5Aclose</code> or resource leaks will develop.
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<dt><strong>Parameters:</strong>
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<dl>
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<dt><em>hid_t</em> <code>loc_id</code>
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<dd>IN: Identifier of the group, dataset, or named datatype
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attribute to be attached to.
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<dt><em>unsigned int</em> <code>idx</code>
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<dd>IN: Index of the attribute to open.
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</dl>
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<dt><strong>Returns:</strong>
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<dd>Returns attribute identifier if successful;
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otherwise returns a negative value.
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<dt><strong>Non-C API(s):</strong>
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<dd><a href="fortran/h5a_FORTRAN.html#h5aopen_idx_f"
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target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
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<!--
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<img src="Graphics/Java.gif">
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<img src="Graphics/C++.gif">
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-->
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</dl>
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<hr>
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<dl>
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<dt><strong>Name:</strong> <a name="Annot-Write">H5Awrite</a>
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<dt><strong>Signature:</strong>
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<dd><em>herr_t</em> <code>H5Awrite</code>(<em>hid_t</em> <code>attr_id</code>,
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<em>hid_t</em> <code>mem_type_id</code>,
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<em>const void *</em><code>buf</code>
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)
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<dt><strong>Purpose:</strong>
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<dd>Writes data to an attribute.
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<dt><strong>Description:</strong>
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<dd><code>H5Awrite</code> writes an attribute, specified with
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<code>attr_id</code>. The attribute's memory datatype
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is specified with <code>mem_type_id</code>. The entire
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attribute is written from <code>buf</code> to the file.
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<p>
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Datatype conversion takes place at the time of a read or write
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and is automatic. See the
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<a href="Datatypes.html#Datatypes-DataConversion">Data Conversion</a>
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section of <cite>The Data Type Interface (H5T)</cite> in the
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<cite>HDF5 User's Guide</cite> for a discussion of
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data conversion, including the range of conversions currently
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supported by the HDF5 libraries.
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<dt><strong>Parameters:</strong>
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<dl>
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<dt><em>hid_t</em> <code>attr_id</code>
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<dd>IN: Identifier of an attribute to write.
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<dt><em>hid_t</em> <code>mem_type_id</code>
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<dd>IN: Identifier of the attribute datatype (in memory).
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<dt><em>const void *</em><code>buf</code>
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<dd>IN: Data to be written.
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</dl>
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<dt><strong>Returns:</strong>
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<dd>Returns a non-negative value if successful;
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otherwise returns a negative value.
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<dt><strong>Non-C API(s):</strong>
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<dd><a href="fortran/h5a_FORTRAN.html#h5awrite_f"
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target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
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<!--
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<img src="Graphics/Java.gif">
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<img src="Graphics/C++.gif">
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-->
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</dl>
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<hr>
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<dl>
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<dt><strong>Name:</strong> <a name="Annot-Read">H5Aread</a>
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<dt><strong>Signature:</strong>
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<dd><em>herr_t</em> <code>H5Aread</code>(<em>hid_t</em> <code>attr_id</code>,
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<em>hid_t</em> <code>mem_type_id</code>,
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<em>void *</em><code>buf</code>
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)
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<dt><strong>Purpose:</strong>
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<dd>Reads an attribute.
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<dt><strong>Description:</strong>
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<dd><code>H5Aread</code> reads an attribute, specified with
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<code>attr_id</code>. The attribute's memory datatype
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is specified with <code>mem_type_id</code>. The entire
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attribute is read into <code>buf</code> from the file.
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<p>
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Datatype conversion takes place at the time of a read or write
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and is automatic. See the
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<a href="Datatypes.html#Datatypes-DataConversion">Data Conversion</a>
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section of <cite>The Data Type Interface (H5T)</cite> in the
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<cite>HDF5 User's Guide</cite> for a discussion of
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data conversion, including the range of conversions currently
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supported by the HDF5 libraries.
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<dt><strong>Parameters:</strong>
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<dl>
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<dt><em>hid_t</em> <code>attr_id</code>
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<dd>IN: Identifier of an attribute to read.
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<dt><em>hid_t</em> <code>mem_type_id</code>
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<dd>IN: Identifier of the attribute datatype (in memory).
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<dt><em>void *</em><code>buf</code>
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<dd>OUT: Buffer for data to be read.
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</dl>
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<dt><strong>Returns:</strong>
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<dd>Returns a non-negative value if successful;
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otherwise returns a negative value.
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<dt><strong>Non-C API(s):</strong>
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<dd><a href="fortran/h5a_FORTRAN.html#h5aread_f"
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target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
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<!--
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<img src="Graphics/Java.gif">
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<img src="Graphics/C++.gif">
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-->
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</dl>
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<hr>
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<dl>
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<dt><strong>Name:</strong> <a name="Annot-GetSpace">H5Aget_space</a>
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<dt><strong>Signature:</strong>
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<dd><em>hid_t</em> <code>H5Aget_space</code>(<em>hid_t</em> <code>attr_id</code>)
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<dt><strong>Purpose:</strong>
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<dd>Gets a copy of the dataspace for an attribute.
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<dt><strong>Description:</strong>
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|
<dd><code>H5Aget_space</code> retrieves a copy of the dataspace
|
|
for an attribute. The dataspace identifier returned from
|
|
this function must be released with <code>H5Sclose</code>
|
|
or resource leaks will develop.
|
|
<dt><strong>Parameters:</strong>
|
|
<dl>
|
|
<dt><em>hid_t</em> <code>attr_id</code>
|
|
<dd>IN: Identifier of an attribute.
|
|
</dl>
|
|
<dt><strong>Returns:</strong>
|
|
<dd>Returns attribute dataspace identifier if successful;
|
|
otherwise returns a negative value.
|
|
<dt><strong>Non-C API(s):</strong>
|
|
<dd><a href="fortran/h5a_FORTRAN.html#h5aget_space_f"
|
|
target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
|
|
<!--
|
|
<img src="Graphics/Java.gif">
|
|
<img src="Graphics/C++.gif">
|
|
-->
|
|
</dl>
|
|
|
|
|
|
<hr>
|
|
<dl>
|
|
<dt><strong>Name:</strong> <a name="Annot-GetType">H5Aget_type</a>
|
|
<dt><strong>Signature:</strong>
|
|
<dd><em>hid_t</em> <code>H5Aget_type</code>(<em>hid_t</em> <code>attr_id</code>)
|
|
<dt><strong>Purpose:</strong>
|
|
<dd>Gets an attribute datatype.
|
|
<dt><strong>Description:</strong>
|
|
<dd><code>H5Aget_type</code> retrieves a copy of the datatype
|
|
for an attribute.
|
|
<p>
|
|
The datatype is reopened if it is a named type before returning
|
|
it to the application. The datatypes returned by this function
|
|
are always read-only. If an error occurs when atomizing the
|
|
return datatype, then the datatype is closed.
|
|
<p>
|
|
The datatype identifier returned from this function must be
|
|
released with <code>H5Tclose</code> or resource leaks will develop.
|
|
<dt><strong>Parameters:</strong>
|
|
<dl>
|
|
<dt><em>hid_t</em> <code>attr_id</code>
|
|
<dd>IN: Identifier of an attribute.
|
|
</dl>
|
|
<dt><strong>Returns:</strong>
|
|
<dd>Returns a datatype identifier if successful;
|
|
otherwise returns a negative value.
|
|
<dt><strong>Non-C API(s):</strong>
|
|
<dd><a href="fortran/h5a_FORTRAN.html#h5aget_type_f"
|
|
target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
|
|
<!--
|
|
<img src="Graphics/Java.gif">
|
|
<img src="Graphics/C++.gif">
|
|
-->
|
|
</dl>
|
|
|
|
|
|
<hr>
|
|
<dl>
|
|
<dt><strong>Name:</strong> <a name="Annot-GetName">H5Aget_name</a>
|
|
<dt><strong>Signature:</strong>
|
|
<dd><em>ssize_t</em> <code>H5Aget_name</code>(<em>hid_t</em> <code>attr_id</code>,
|
|
<em>size_t</em> <code>buf_size</code>,
|
|
<em>char *</em><code>buf</code>
|
|
)
|
|
<dt><strong>Purpose:</strong>
|
|
<dd>Gets an attribute name.
|
|
<dt><strong>Description:</strong>
|
|
<dd><code>H5Aget_name</code> retrieves the name of an attribute
|
|
specified by the identifier, <code>attr_id</code>.
|
|
Up to <code>buf_size</code> characters are stored in
|
|
<code>buf</code> followed by a <code>\0</code> string
|
|
terminator. If the name of the attribute is longer than
|
|
<code>(buf_size -1)</code>, the string terminator is stored in the
|
|
last position of the buffer to properly terminate the string.
|
|
<dt><strong>Parameters:</strong>
|
|
<dl>
|
|
<dt><em>hid_t</em> <code>attr_id</code>
|
|
<dd>IN: Identifier of the attribute.
|
|
<dt><em>size_t</em> <code>buf_size</code>
|
|
<dd>IN: The size of the buffer to store the name in.
|
|
<dt><em>char *</em><code>buf</code>
|
|
<dd>IN: Buffer to store name in.
|
|
</dl>
|
|
<dt><strong>Returns:</strong>
|
|
<dd>Returns the length of the attribute's name, which may be
|
|
longer than <code>buf_size</code>, if successful.
|
|
Otherwise returns a negative value.
|
|
<dt><strong>Non-C API(s):</strong>
|
|
<dd><a href="fortran/h5a_FORTRAN.html#h5aget_name_f"
|
|
target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
|
|
<!--
|
|
<img src="Graphics/Java.gif">
|
|
<img src="Graphics/C++.gif">
|
|
-->
|
|
</dl>
|
|
|
|
|
|
<hr>
|
|
<dl>
|
|
<dt><strong>Name:</strong> <a name="Annot-NumAttrs">H5Aget_num_attrs</a>
|
|
<dt><strong>Signature:</strong>
|
|
<dd><em>int</em> <code>H5Aget_num_attrs</code>(<em>hid_t</em> <code>loc_id</code>)
|
|
<dt><strong>Purpose:</strong>
|
|
<dd>Determines the number of attributes attached to an object.
|
|
<dt><strong>Description:</strong>
|
|
<dd><code>H5Aget_num_attrs</code> returns the number of attributes
|
|
attached to the object specified by its identifier,
|
|
<code>loc_id</code>.
|
|
The object can be a group, dataset, or named datatype.
|
|
<dt><strong>Parameters:</strong>
|
|
<dl>
|
|
<dt><em>hid_t</em> <code>loc_id</code>
|
|
<dd>IN: Identifier of a group, dataset, or named datatype.
|
|
</dl>
|
|
<dt><strong>Returns:</strong>
|
|
<dd>Returns the number of attributes if successful;
|
|
otherwise returns a negative value.
|
|
<dt><strong>Non-C API(s):</strong>
|
|
<dd><a href="fortran/h5a_FORTRAN.html#h5aget_num_attrs_f"
|
|
target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
|
|
<!--
|
|
<img src="Graphics/Java.gif">
|
|
<img src="Graphics/C++.gif">
|
|
-->
|
|
</dl>
|
|
|
|
|
|
<hr>
|
|
<dl>
|
|
<dt><strong>Name:</strong> <a name="Annot-Iterate">H5Aiterate</a>
|
|
<dt><strong>Signature:</strong>
|
|
<dd><em>herr_t</em> <code>H5Aiterate</code>(<em>hid_t</em> <code>loc_id</code>,
|
|
<em>unsigned *</em> <code>idx</code>,
|
|
<em>H5A_operator_t</em> <code>op</code>,
|
|
<em>void *</em><code>op_data</code>
|
|
)
|
|
<dt><strong>Purpose:</strong>
|
|
<dd>Calls a user's function for each attribute on an object.
|
|
<dt><strong>Description:</strong>
|
|
<dd><code>H5Aiterate</code> iterates over the attributes of
|
|
the object specified by its identifier, <code>loc_id</code>.
|
|
The object can be a group, dataset, or named datatype.
|
|
For each attribute of the object, the <code>op_data</code>
|
|
and some additional information specified below are passed
|
|
to the operator function <code>op</code>.
|
|
The iteration begins with the attribute specified by its
|
|
index, <code>idx</code>; the index for the next attribute
|
|
to be processed by the operator, <code>op</code>, is
|
|
returned in <code>idx</code>.
|
|
If <code>idx</code> is the null pointer, then all attributes
|
|
are processed.
|
|
<p>
|
|
The prototype for <code>H5A_operator_t</code> is: <br>
|
|
<code>typedef herr_t (*H5A_operator_t)(hid_t <em>loc_id</em>,
|
|
const char *<em>attr_name</em>,
|
|
void *<em>operator_data</em>);
|
|
</code>
|
|
<p>
|
|
The operation receives the identifier for the group, dataset
|
|
or named datatype being iterated over, <code>loc_id</code>, the
|
|
name of the current attribute about the object, <code>attr_name</code>,
|
|
and the pointer to the operator data passed in to <code>H5Aiterate</code>,
|
|
<code>op_data</code>. The return values from an operator are:
|
|
<ul>
|
|
<li>Zero causes the iterator to continue, returning zero when all
|
|
attributes have been processed.
|
|
<li>Positive causes the iterator to immediately return that positive
|
|
value, indicating short-circuit success. The iterator can be
|
|
restarted at the next attribute.
|
|
<li>Negative causes the iterator to immediately return that value,
|
|
indicating failure. The iterator can be restarted at the next
|
|
attribute.
|
|
</ul>
|
|
<dt><strong>Parameters:</strong>
|
|
<dl>
|
|
<dt><em>hid_t</em> <code>loc_id</code>
|
|
<dd>IN: Identifier of a group, dataset or named datatype.
|
|
<dt><em>unsigned *</em> <code>idx</code>
|
|
<dd>IN/OUT: Starting (IN) and ending (OUT) attribute index.
|
|
<dt><em>H5A_operator_t</em> <code>op</code>
|
|
<dd>IN: User's function to pass each attribute to
|
|
<dt><em>void *</em><code>op_data</code>
|
|
<dd>IN/OUT: User's data to pass through to iterator operator function
|
|
</dl>
|
|
<dt><strong>Returns:</strong>
|
|
<dd>If successful, returns the return value of the last operator
|
|
if it was non-zero, or zero if all attributes were processed.
|
|
Otherwise returns a negative value.
|
|
<!--
|
|
<dt><strong>Non-C API(s):</strong>
|
|
<dd><a href="fortran/h5a_FORTRAN.html#h5aiterate_f"
|
|
target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
|
|
--> <!--
|
|
<img src="Graphics/Java.gif">
|
|
<img src="Graphics/C++.gif">
|
|
-->
|
|
</dl>
|
|
|
|
|
|
<hr>
|
|
<dl>
|
|
<dt><strong>Name:</strong> <a name="Annot-Delete">H5Adelete</a>
|
|
<dt><strong>Signature:</strong>
|
|
<dd><em>herr_t</em> <code>H5Adelete</code>(<em>hid_t</em> <code>loc_id</code>,
|
|
<em>const char *</em><code>name</code>
|
|
)
|
|
<dt><strong>Purpose:</strong>
|
|
<dd>Deletes an attribute from a location.
|
|
<dt><strong>Description:</strong>
|
|
<dd><code>H5Adelete</code> removes the attribute specified by its
|
|
name, <code>name</code>, from a dataset, group, or named datatype.
|
|
This function should not be used when attribute identifiers are
|
|
open on <code>loc_id</code> as it may cause the internal indexes
|
|
of the attributes to change and future writes to the open
|
|
attributes to produce incorrect results.
|
|
<dt><strong>Parameters:</strong>
|
|
<dl>
|
|
<dt><em>hid_t</em> <code>loc_id</code>
|
|
<dd>IN: Identifier of the dataset, group, or named datatype
|
|
to have the attribute deleted from.
|
|
<dt><em>const char *</em><code>name</code>
|
|
<dd>IN: Name of the attribute to delete.
|
|
</dl>
|
|
<dt><strong>Returns:</strong>
|
|
<dd>Returns a non-negative value if successful;
|
|
otherwise returns a negative value.
|
|
<dt><strong>Non-C API(s):</strong>
|
|
<dd><a href="fortran/h5a_FORTRAN.html#h5adelete_f"
|
|
target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
|
|
<!--
|
|
<img src="Graphics/Java.gif">
|
|
<img src="Graphics/C++.gif">
|
|
-->
|
|
</dl>
|
|
|
|
|
|
<hr>
|
|
<dl>
|
|
<dt><strong>Name:</strong> <a name="Annot-Close">H5Aclose</a>
|
|
<dt><strong>Signature:</strong>
|
|
<dd><em>herr_t</em> <code>H5Aclose</code>(<em>hid_t</em> <code>attr_id</code>)
|
|
<dt><strong>Purpose:</strong>
|
|
<dd>Closes the specified attribute.
|
|
<dt><strong>Description:</strong>
|
|
<dd><code>H5Aclose</code> terminates access to the attribute
|
|
specified by <code>attr_id</code> by releasing the identifier.
|
|
<p>
|
|
Further use of a released attribute identifier is illegal;
|
|
a function using such an identifier will fail.
|
|
<dt><strong>Parameters:</strong>
|
|
<dl>
|
|
<dt><em>hid_t</em> <code>attr_id</code>
|
|
<dd>IN: Attribute to release access to.
|
|
</dl>
|
|
<dt><strong>Returns:</strong>
|
|
<dd>Returns a non-negative value if successful;
|
|
otherwise returns a negative value.
|
|
<dt><strong>Non-C API(s):</strong>
|
|
<dd><a href="fortran/h5a_FORTRAN.html#h5aclose_f"
|
|
target="FortranWin"><img src="Graphics/FORTRAN.gif" border=0></a>
|
|
<!--
|
|
<img src="Graphics/Java.gif">
|
|
<img src="Graphics/C++.gif">
|
|
-->
|
|
</dl>
|
|
|
|
|
|
<!-- #BeginLibraryItem "/ed_libs/NavBar_RM.lbi" --><hr>
|
|
<center>
|
|
<table border=0 width=98%>
|
|
<tr><td valign=top align=left>
|
|
<a href="index.html">HDF5 documents and links</a> <br>
|
|
<a href="H5.intro.html">Introduction to HDF5</a> <br>
|
|
<a href="H5.user.html">HDF5 User Guide</a> <br>
|
|
<!--
|
|
<a href="Glossary.html">Glossary</a><br>
|
|
-->
|
|
</td>
|
|
<td valign=top align=right>
|
|
And in this document, the
|
|
<a href="RM_H5Front.html">HDF5 Reference Manual</a>
|
|
<br>
|
|
<a href="RM_H5.html">H5</a>
|
|
<a href="RM_H5A.html">H5A</a>
|
|
<a href="RM_H5D.html">H5D</a>
|
|
<a href="RM_H5E.html">H5E</a>
|
|
<a href="RM_H5F.html">H5F</a>
|
|
<a href="RM_H5G.html">H5G</a>
|
|
<a href="RM_H5I.html">H5I</a>
|
|
<a href="RM_H5P.html">H5P</a>
|
|
<br>
|
|
<a href="RM_H5R.html">H5R</a>
|
|
<a href="RM_H5S.html">H5S</a>
|
|
<a href="RM_H5T.html">H5T</a>
|
|
<a href="RM_H5Z.html">H5Z</a>
|
|
<a href="Tools.html">Tools</a>
|
|
<a href="PredefDTypes.html">Datatypes</a>
|
|
</td></tr>
|
|
</table>
|
|
</center>
|
|
<hr>
|
|
<!-- #EndLibraryItem --><!-- #BeginLibraryItem "/ed_libs/Footer.lbi" --><address>
|
|
<a href="mailto:hdfhelp@ncsa.uiuc.edu">HDF Help Desk</a>
|
|
<br>
|
|
Describes HDF5 Release 1.5, Unreleased Development Branch
|
|
</address><!-- #EndLibraryItem -->
|
|
|
|
Last modified: 6 June 2001
|
|
|
|
</body>
|
|
</html>
|