hdf5/doc/html/RM_H5P.html
Frank Baker c8e75d27b0 [svn-r503] HDF5 Reference Manual
Updated for Alpha2.
1998-07-14 23:51:50 -05:00

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<html>
<head><title>
HDF5/H5P Draft API Specification
</title></head>
<body>
<hr>
<center>
<a href="RM_H5Front.html">HDF5 Reference Manual</a>&nbsp;
<a href="RM_H5.html">H5</a>&nbsp;&nbsp;
<a href="RM_H5A.html">H5A</a>&nbsp;&nbsp;
<a href="RM_H5D.html">H5D</a>&nbsp;&nbsp;
<a href="RM_H5E.html">H5E</a>&nbsp;&nbsp;
<a href="RM_H5F.html">H5F</a>&nbsp;&nbsp;
<a href="RM_H5G.html">H5G</a>&nbsp;&nbsp;
H5P&nbsp;&nbsp;
<a href="RM_H5S.html">H5S</a>&nbsp;&nbsp;
<a href="RM_H5T.html">H5T</a>&nbsp;&nbsp;
<a href="RM_H5Z.html">H5Z</a>&nbsp;&nbsp;
<a href="Glossary.html">Glossary</a>
</center>
<hr>
<center>
<h1>H5P: Property List Interface</h1>
</center>
<h2>Property List API Functions</h2>
These functions manipulate property list objects to allow objects which require
many different parameters to be easily manipulated.
<dir>
<table border=0>
<tr><td valign=top>
<i>General Property List Operations</i>
<ul>
<li><a href="#Property-Create">H5Pcreate</a>
<li><a href="#Property-GetClass">H5Pget_class</a>
<li><a href="#Property-Copy">H5Pcopy</a>
<li><a href="#Property-Close">H5Pclose</a>
</ul>
<p><i>File Creation Properties</i>
<ul>
<li><a href="#Property-GetVersion">H5Pget_version</a>
<li><a href="#Property-SetUserblock">H5Pset_userblock</a>
<li><a href="#Property-GetUserblock">H5Pget_userblock</a>
<li><a href="#Property-SetSizes">H5Pset_sizes</a>
<li><a href="#Property-GetSizes">H5Pget_sizes</a>
<li><a href="#Property-SetSymK">H5Pset_sym_k</a>
<li><a href="#Property-GetSymK">H5Pget_sym_k</a>
<li><a href="#Property-SetIstoreK">H5Pset_istore_k</a>
<li><a href="#Property-GetIstoreK">H5Pget_istore_k</a>
</ul>
</td><td>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</td><td valign=top>
<i>File Access Properties</i>
<ul>
<li><a href="#Property-GetDriver">H5Pget_driver</a>
<li><a href="#Property-SetStdio">H5Pset_stdio</a>
<li><a href="#Property-GetStdio">H5Pget_stdio</a>
<li><a href="#Property-SetSec2">H5Pset_sec2</a>
<li><a href="#Property-GetSec2">H5Pget_sec2</a>
<li><a href="#Property-SetAlignment">H5Pset_alignment</a>
<li><a href="#Property-GetAlignment">H5Pget_alignment</a>
<li><a href="#Property-SetCore">H5Pset_core</a>
<li><a href="#Property-GetCore">H5Pget_core</a>
<li><a href="#Property-SetMPI">H5Pset_mpi</a>&nbsp;&nbsp;&nbsp;||
<li><a href="#Property-GetMPI">H5Pget_mpi</a>&nbsp;&nbsp;&nbsp;||
<li><a href="#Property-SetFamily">H5Pset_family</a>
<li><a href="#Property-GetFamily">H5Pget_family</a>
<li><a href="#Property-SetCache">H5Pset_cache</a>
<li><a href="#Property-GetCache">H5Pget_cache</a>
<li><a href="#Property-SetSplit">H5Pset_split</a>
<li><a href="#Property-GetSplit">H5Pget_split</a>
</ul>
</td><td>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</td><td valign=top>
<i>Dataset Creation Properties</i>
<ul>
<li><a href="#Property-SetLayout">H5Pset_layout</a>
<li><a href="#Property-GetLayout">H5Pget_layout</a>
<li><a href="#Property-SetChunk">H5Pset_chunk</a>
<li><a href="#Property-GetChunk">H5Pget_chunk</a>
<li><a href="#Property-SetDeflate">H5Pset_deflate</a>
<li><a href="#Property-GetDeflate">H5Pget_deflate</a>
<li><a href="#Property-SetCompression">H5Pset_compression</a>
<li><a href="#Property-GetCompression">H5Pget_compression</a>
<li><a href="#Property-SetExternal">H5Pset_external</a>
<li><a href="#Property-GetExternalCount">H5Pget_external_count</a>
<li><a href="#Property-GetExternal">H5Pget_external</a>
</ul>
<p><i>Dataset Memory and Transfer Properties</i>
<ul>
<li><a href="#Property-SetBuffer">H5Pset_buffer</a>
<li><a href="#Property-GetBuffer">H5Pget_buffer</a>
<li><a href="#Property-SetPreserve">H5Pset_preserve</a>
<li><a href="#Property-GetPreserve">H5Pget_preserve</a>
<li><a href="#Property-SetXfer">H5Pset_xfer</a>&nbsp;&nbsp;&nbsp;||
<li><a href="#Property-GetXfer">H5Pget_xfer</a>&nbsp;&nbsp;&nbsp;||
</ul>
</td></tr>
<tr><td colspan=5 align=right>
<br>
||&nbsp;&nbsp;&nbsp;<i>Available only in the parallel HDF5 library.</i>
</td></tr>
</table>
</dir
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-Create">H5Pcreate</a>
<dt><strong>Signature:</strong>
<dd><em>hid_t </em><code>H5Pcreate</code>(<em>H5P_class_t</em> <code>type</code>
)
<dt><strong>Purpose:</strong>
<dd>Creates a new property as an instance of a property list class.
<dt><strong>Description:</strong>
<dd><code>H5Pcreate</code> creates a new property as an instance of some
property list class. The new property list is initialized
with default values for the specified class. The classes are:
<dl>
<dt><code>H5P_FILE_CREATE</code>
<dd>Properties for file creation.
See <a href="Files.html">Files</a>
in the <cite>HDF User's Guide</cite>
for details about the file creation properties.
<dt><code>H5P_FILE_ACCESS</code>
<dd>Properties for file access.
See <a href="Files.html">Files</a>
in the <cite>HDF User's Guide</cite>
for details about the file creation properties.
<dt><code>H5P_DATASET_CREATE</code>
<dd>Properties for dataset creation.
See <a href="Datasets.html">Datasets</a>
in the <cite>HDF User's Guide</cite>
for details about dataset creation properties.
<dt><code>H5P_DATASET_XFER</code>
<dd>Properties for raw data transfer.
See <a href="Datasets.html">Datasets</a>
in the <cite>HDF User's Guide</cite>
for details about raw data transfer properties.
</dl>
<dt><strong>Parameters:</strong>
<dl>
<dt><em>H5P_class_t</em> <code>type</code>
<dd>IN: The type of property list to create.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns a property list identifier (<code>plist</code>) if successful;
otherwise Fail (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-Close">H5Pclose</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pclose</code>(<em>hid_t</em> <code>plist</code>
)
<dt><strong>Purpose:</strong>
<dd>Terminates access to a property list.
<dt><strong>Description:</strong>
<dd><code>H5Pclose</code> terminates access to a property list.
All property lists should be closed when the application is
finished accessing them.
This frees resources used by the property list.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the property list to terminate access to.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetClass">H5Pget_class</a>
<dt><strong>Signature:</strong>
<dd><em>H5P_class_t </em><code>H5Pget_class</code>(<em>hid_t</em> <code>plist</code>
)
<dt><strong>Purpose:</strong>
<dd>Returns the property list class for a property list.
<dt><strong>Description:</strong>
<dd><code>H5Pget_class</code> returns the property list class for the
property list identied by the <code>plist</code> parameter.
Valid property list classes are defined in the description of
<code>H5Pcreate()</code>.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to query.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns a property list class if successful.
Otherwise returns H5P_NO_CLASS (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-Copy">H5Pcopy</a>
<dt><strong>Signature:</strong>
<dd><em>hid_t </em><code>H5Pcopy</code>(<em>hid_t</em> <code>plist</code>
)
<dt><strong>Purpose:</strong>
<dd>Copies an existing property list to create a new property list.
<dt><strong>Description:</strong>
<dd><code>H5Pcopy</code> copies an existing property list to create
a new property list.
The new property list has the same properties and values
as the original property list.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to duplicate.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns a property list identifier if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetVersion">H5Pget_version</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pget_version</code>(<em>hid_t</em> <code>plist</code>,
<em>int *</em> <code>boot</code>,
<em>int *</em> <code>freelist</code>,
<em>int *</em> <code>stab</code>,
<em>int *</em> <code>shhdr</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the version information of various objects for
a file creation property list.
<dt><strong>Description:</strong>
<dd><code>H5Pget_version</code> retrieves the version information of various objects
for a file creation property list. Any pointer parameters which are
passed as NULL are not queried.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file creation property list.
<dt><em>int *</em> <code>boot</code>
<dd>OUT: Pointer to location to return boot block version number.
<dt><em>int *</em> <code>freelist</code>
<dd>OUT: Pointer to location to return global freelist version number.
<dt><em>int *</em> <code>stab</code>
<dd>OUT: Pointer to location to return symbol table version number.
<dt><em>int *</em> <code>shhdr</code>
<dd>OUT: Pointer to location to return shared object header version number.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetUserblock">H5Pset_userblock</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_userblock</code>(<em>hid_t</em> <code>plist</code>,
<em>hsize_t</em> <code>size</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets user block size.
<dt><strong>Description:</strong>
<dd><code>H5Pset_userblock</code> sets the user block size of a
file creation property list.
The default user block size is 0; it may be set to any
power of 2 equal to 512 or greater (512, 1024, 2048, etc.).
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to modify.
<dt><em>hsize_t</em> <code>size</code>
<dd>IN: Size of the user-block in bytes.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetUserblock">H5Pget_userblock</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pget_userblock</code>(<em>hid_t</em> <code>plist</code>,
<em>hsize_t *</em> <code>size</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the size of a user block.
<dt><strong>Description:</strong>
<dd><code>H5Pget_userblock</code> retrieves the size of a user block
in a file creation property list.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for property list to query.
<dt><em>hsize_t *</em> <code>size</code>
<dd>OUT: Pointer to location to return user-block size.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetSizes">H5Pset_sizes</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_sizes</code>(<em>hid_t</em> <code>plist</code>,
<em>size_t</em> <code>sizeof_addr</code>,
<em>size_t</em> <code>sizeof_size</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the byte size of the offsets and lengths used to address objects
in an HDF5 file.
<dt><strong>Description:</strong>
<dd><code>H5Pset_sizes</code> sets the byte size of the offsets and lengths used to
address objects in an HDF5 file. This function is only valid for
file creation property lists. Passing in a value of 0 for one of the
sizeof parameters retains the current value. The default value
for both values is 4 bytes. Valid values currenly are 2, 4, 8 and
16.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to modify.
<dt><em>size_t</em> <code>sizeof_addr</code>
<dd>IN: Size of an object offset in bytes.
<dt><em>size_t</em> <code>sizeof_size</code>
<dd>IN: Size of an object length in bytes.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetSizes">H5Pget_sizes</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pget_sizes</code>(<em>hid_t</em> <code>plist</code>,
<em>size_t *</em> <code>sizeof_addr</code>,
<em>size_t *</em> <code>sizeof_size</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the size of the offsets and lengths used in an HDF5 file.
<dt><strong>Description:</strong>
<dd><code>H5Pget_sizes</code> retrieves the size of the offsets
and lengths used in an HDF5 file.
This function is only valid for file creation property lists.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to query.
<dt><em>size_t *</em> <code>size</code>
<dd>OUT: Pointer to location to return offset size in bytes.
<dt><em>size_t *</em> <code>size</code>
<dd>OUT: Pointer to location to return length size in bytes.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetMPI">H5Pset_mpi</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_mpi</code>(<em>hid_t</em> <code>plist</code>,
<em>MPI_Comm</em> <code>comm</code>,
<em>MPI_Info</em> <code>info</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the access mode for parallel I/O and the user supplied
communicator and info object.
<dt><strong>Description:</strong>
<dd><code>H5Pset_mpi</code> stores the access mode for MPIO call and the user supplied
communicator and info in the access property list, which can then
be used to open file. This function is available only in the
parallel HDF5 library and is not a collective function.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to modify
<dt><em>MPI_Comm</em> <code>comm</code>
<dd>IN: MPI communicator to be used for file open as defined in
MPI_FILE_OPEN of MPI-2. This function does not make a
duplicated <code>comm</code>. Any modification to <code>comm</code> after
this function call returns may have undetermined effect
to the access property list. Users should call this function
again to setup the property list.
<dt><em>MPI_Info</em> <code>info</code>
<dd>IN: MPI info object to be used for file open as defined in
MPI_FILE_OPEN of MPI-2. This function does not make a
duplicated <code>info</code>. Any modification to <code>info</code> after
this function call returns may have undetermined effect
to the access property list. Users should call this function
again to setup the property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetMPI">H5Pget_mpi</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pget_mpi</code>(<em>hid_t</em> <code>plist</code>,
<em>MPI_Comm</em> <code>*comm</code>,
<em>MPI_Info</em> <code>*info</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the communicator and info object.
<dt><strong>Description:</strong>
<dd><code>H5Pget_mpi</code> retrieves the communicator and info object
that have been set by H5Pset_mpi.
This function is available only in the parallel HDF5 library
and is not a collective function.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list that has been set
successfully by H5Pset_mpi.
<dt><em>MPI_Comm *</em> <code>comm</code>
<dd>OUT: Pointer to location to return the communicator.
<dt><em>MPI_Info *</em> <code>info</code>
<dd>OUT: Pointer to location to return the info object.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if the file access property list is set to the MPI.
Otherwise returns FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetXfer">H5Pset_xfer</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_xfer</code>(<em>hid_t</em> <code>plist</code>,
<em>H5D_transfer_t</em> <code>data_xfer_mode</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the transfer mode of the dataset transfer property list.
<dt><strong>Description:</strong>
<dd><code>H5Pset_xfer</code> sets the transfer mode of the dataset transfer property list.
The list can then be used to control the I/O transfer mode
during dataset accesses. This function is available only
in the parallel HDF5 library and is not a collective function.
<p>
Valid data transfer modes are:
<ul><dl>
<dt>H5D_XFER_INDEPENDENT
<dd>Use independent I/O access.
(Currently the default mode.)
<dt>H5D_XFER_COLLECTIVE
<dd>Use MPI collective I/O access.
<dt>H5D_XFER_DFLT
<dd>User default I/O access.
</dl></ul>
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a dataset transfer property list
<dt><em>H5D_transfer_t</em> <code>data_xfer_mode</code>
<dd>IN: Data transfer mode.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetXfer">H5Pget_xfer</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pget_xfer</code>(<em>hid_t</em> <code>plist</code>,
<em>H5D_transfer_t *</em> <code>data_xfer_mode</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the transfer mode from the dataset transfer property list.
<dt><strong>Description:</strong>
<dd><code>H5Pget_xfer</code> retrieves the transfer mode from the dataset
transfer property list.
This function is available only in the parallel HDF5 library
and is not a collective function.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a dataset transfer property list.
<dt><em>H5D_transfer_t *</em> <code>data_xfer_mode</code>
<dd>OUT: Pointer to location to return the data transfer mode.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetSymK">H5Pset_sym_k</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_sym_k</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>ik</code>,
<em>int</em> <code>lk</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the size of parameters used to control the symbol table nodes.
<dt><strong>Description:</strong>
<dd><code>H5Pset_sym_k</code> sets the size of parameters used to control the
symbol table nodes. This function is only valid for
file creation property lists. Passing in a value of 0 for one of the
parameters retains the current value.
<p>
<code>ik</code> is one half the rank of a tree that stores a symbol
table for a group. Internal nodes of the symbol table are on
average 75% full. That is, the average rank of the tree is
1.5 times the value of <code>ik</code>.
<p>
<code>lk</code> is one half of the number of symbols that can be stored in
a symbol table node. A symbol table node is the leaf of a
symbol table tree which is used to store a group. When
symbols are inserted randomly into a group, the group's
symbol table nodes are 75% full on average. That is, they
contain 1.5 times the number of symbols specified by <code>lk</code>.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for property list to query.
<dt><em>int</em> <code>ik</code>
<dd>IN: Symbol table tree rank.
<dt><em>int</em> <code>lk</code>
<dd>IN: Symbol table node size.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetSymK">H5Pget_sym_k</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pget_sym_k</code>(<em>hid_t</em> <code>plist</code>,
<em>int *</em> <code>ik</code>,
<em>int *</em> <code>lk</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the size of the symbol table B-tree 1/2 rank
and the symbol table leaf node 1/2 size.
<dt><strong>Description:</strong>
<dd><code>H5Pget_sym_k</code> retrieves the size of the
symbol table B-tree 1/2 rank and the symbol table leaf node 1/2 size.
This function is only valid for file creationproperty lists.
If a parameter valued is set to NULL, that parameter is not retrieved.
See the description for <a href="#Property-SetSymK">H5Pset_sym_k</a>
for more information.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Property list to query.
<dt><em>int *</em> <code>ik</code>
<dd>OUT: Pointer to location to return the symbol table's B-tree 1/2 rank.
<dt><em>int *</em> <code>size</code>
<dd>OUT: Pointer to location to return the symbol table's leaf node 1/2 size.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetIstoreK">H5Pset_istore_k</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_istore_k</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>ik</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the size of the parameter used to control the
B-trees for indexing chunked datasets.
<dt><strong>Description:</strong>
<dd><code>H5Pset_istore_k</code> sets the size of the parameter used to control the
B-trees for indexing chunked datasets. This function is only valid for
file creation property lists. Passing in a value of 0 for one of the
parameters retains the current value.
<p>
<code>ik</code> is one half the rank of a tree that stores chunked raw
data. On average, such a tree will be 75% full, or have an
average rank of 1.5 times the value of <code>ik</code>.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to query.
<dt><em>int</em> <code>ik</code>
<dd>IN: 1/2 rank of chunked storage B-tree.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetIstoreK">H5Pget_istore_k</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pget_istore_k</code>(<em>hid_t</em> <code>plist</code>,
<em>int *</em> <code>ik</code>
)
<dt><strong>Purpose:</strong>
<dd>Queries the 1/2 rank of an indexed storage B-tree.
<dt><strong>Description:</strong>
<dd><code>H5Pget_istore_k</code> queries the 1/2 rank of
an indexed storage B-tree.
The argument <code>ik</code> may be the null pointer (NULL).
This function is only valid for file creation property lists.
<p>
See <a href="#Property-SetIstoreK">H5Pset_istore_k</a> for details.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to query.
<dt><em>int *</em> <code>ik</code>
<dd>OUT: Pointer to location to return the chunked storage B-tree 1/2 rank.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetLayout">H5Pset_layout</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_layout</code>(<em>hid_t</em> <code>plist</code>,
<em>H5D_layout_t</em> <code>layout</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the type of storage used store the raw data for a dataset.
<dt><strong>Description:</strong>
<dd><code>H5Pset_layout</code> sets the type of storage used store the
raw data for a dataset.
This function is only valid for dataset creation property lists.
Valid parameters for <code>layout</code> are:
<ul><dl>
<dt>H5D_COMPACT
<dd>Store raw data and object header contiguously in file.
This should only be used for very small amounts of raw
data (suggested less than 1KB).
<dt>H5D_CONTIGUOUS
<dd>Store raw data seperately from object header in one
large chunk in the file.
<dt>H5D_CHUNKED
<dd>Store raw data seperately from object header in one
large chunk in the file and store chunks of the raw
data in seperate locations in the file.
</dl></ul>
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to query.
<dt><em>H5D_layout_t</em> <code>layout</code>
<dd>IN: Type of storage layout for raw data.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetLayout">H5Pget_layout</a>
<dt><strong>Signature:</strong>
<dd><em>H5D_layout_t</em> <code>H5Pget_layout</code>(<em>hid_t</em> <code>plist</code>)
<dt><strong>Purpose:</strong>
<dd>Returns the layout of the raw data for a dataset.
<dt><strong>Description:</strong>
<dd><code>H5Pget_layout</code> returns the layout of the raw data for a dataset.
This function is only valid for dataset creation property lists.
Valid types for <code>layout</code> are:
<ul> <dl>
<dt>H5D_COMPACT
<dd>Raw data and object header stored contiguously in file.
<dt>H5D_CONTIGUOUS
<dd>Raw data stored seperately from object header in one
large chunk in the file.
<dt>H5D_CHUNKED
<dd>Raw data stored seperately from object header in
chunks in seperate locations in the file.
</dl> </ul>
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for property list to query.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns the layout type of a a dataset creation property list
if successful.
Otherwise returns H5D_LAYOUT_ERROR (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetChunk">H5Pset_chunk</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t </em><code>H5Pset_chunk</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>ndims</code>,
<em>const hsize_t *</em> <code>dim</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the size of the chunks used to store a chunked layout dataset.
<dt><strong>Description:</strong>
<dd><code>H5Pset_chunk</code> sets the size of the chunks used to store a chunked
layout dataset. This function is only valid for dataset creation
property lists. The <code>ndims</code> parameter currently must be the
same size as the rank of the dataset. The values of the
<code>dim</code> array define the size of the chunks to store the
dataset's raw data. As a side-effect, the layout of the dataset is
changed to H5D_CHUNKED, if it isn't already.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for property list to query.
<dt><em>int</em> <code>ndims</code>
<dd>IN: The number of dimensions of each chunk.
<dt><em>const hsize_t *</em> <code>dim</code>
<dd>IN: An array containing the size of each chunk.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetChunk">H5Pget_chunk</a>
<dt><strong>Signature:</strong>
<dd><em>int </em><code>H5Pget_chunk</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>max_ndims</code>,
<em>hsize_t *</em> <code>dims</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the size of chunks for the raw data of a chunked layout dataset.
<dt><strong>Description:</strong>
<dd><code>H5Pget_chunk</code> retrieves the size of chunks for the
raw data of a chunked layout dataset.
This function is only valid for dataset creation property lists.
At most, <code>max_ndims</code> elements of <code>dims</code>
will be initialized.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of property list to query.
<dt><em>int</em> <code>max_ndims</code>
<dd>OUT: Size of the <code>dims</code> array.
<dt><em>hsize_t *</em> <code>dims</code>
<dd>OUT: Array to store the chunk dimensions.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns chunk dimensionality successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetAlignment">H5Pset_alignment</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_alignment</code>(<em>hid_t</em> <code>plist</code>,
<em>hsize_t</em> <code>threshold</code>,
<em>hsize_t</em> <code>alignment</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets alignment properties of a file access property list.
<dt><strong>Description:</strong>
<dd><code>H5Pset_alignment</code> sets the alignment properties
of a file access property list
so that any file object >= THRESHOLD bytes will be aligned on
an address which is a multiple of ALIGNMENT. The addresses
are relative to the end of the user block; the alignment is
calculated by subtracting the user block size from the
absolute file address and then adjusting the address to be a
multiple of ALIGNMENT.
<p>
Default values for THRESHOLD and ALIGNMENT are one, implying
no alignment. Generally the default values will result in
the best performance for single-process access to the file.
For MPI-IO and other parallel systems, choose an alignment
which is a multiple of the disk block size.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for a file access property list.
<dt><em>hsize_t</em> <code>threshold</code>
<dd>IN: Threshhold value.
<dt><em>hsize_t</em> <code>alignment</code>
<dd>IN: Alignment value.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetAlignment">H5Pget_alignment</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pget_alignment</code>(<em>hid_t</em> <code>plist</code>,
<em>hsize_t</em> <code>*threshold</code>,
<em>hsize_t</em> <code>*alignment</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves the current settings for alignment properties from a
file access property list.
<dt><strong>Description:</strong>
<dd><code>H5Pget_alignment</code> retrieves the current settings for
alignment properties from a file access property list.
The <code>threshold</code> and/or <code>alignment</code> pointers
may be null pointers (NULL).
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list.
<dt><em>hsize_t</em> <code>*threshold</code>
<dd>OUT: Pointer to location of return threshhold value.
<dt><em>hsize_t</em> <code>*alignment</code>
<dd>OUT: Pointer to location of return alignment value.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetExternal">H5Pset_external</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_external</code>(<em>hid_t</em> <code>plist</code>,
<em>const char</em> <code>*name</code>,
<em>off_t</em> <code>offset</code>,
<em>hsize_t</em> <code>size</code>
)
<dt><strong>Purpose:</strong>
<dd>Adds an external file to the list of external files.
<dt><strong>Description:</strong>
<dd><code>H5Pset_external</code> adds an external file to the
list of external files.
<p>
If a dataset is split across multiple files then the files
should be defined in order. The total size of the dataset is
the sum of the SIZE arguments for all the external files. If
the total size is larger than the size of a dataset then the
dataset can be extended (provided the data space also allows
the extending).
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a dataset creation property list.
<dt><em>const char</em> <code>*name</code>
<dd>IN: Name of an external file.
<dt><em>off_t</em> <code>offset</code>
<dd>IN: Offset, in bytes, from the beginning of the file
to the location in the file where the data starts.
<dt><em>hsize_t</em> <code>size</code>
<dd>IN: Number of bytes reserved in the file for the data.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetExternalCount">H5Pget_external_count</a>
<dt><strong>Signature:</strong>
<dd><em>int</em> <code>H5Pget_external_count</code>(<em>hid_t</em> <code>plist</code>,
)
<dt><strong>Purpose:</strong>
<dd>Returns the number of external files for a dataset.
<dt><strong>Description:</strong>
<dd><code>H5Pget_external_count</code> returns the number of external files
for the specified dataset.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a dataset creation property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns the number of external files if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetExternal">H5Pget_external</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pget_external</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>idx</code>,
<em>size_t</em> <code>name_size</code>,
<em>char</em> <code>*name</code>,
<em>off_t</em> <code>*offset</code>,
<em>hsize_t</em> <code>*size</code>
)
<dt><strong>Purpose:</strong>
<dd>Returns information about an external file.
<dt><strong>Description:</strong>
<dd><code>H5Pget_external</code> returns information about an external file.
The external file is specified by its index, <code>idx</code>,
which is a number from zero to N-1, where N is the value
returned by <code>H5Pget_external_count()</code>.
At most <code>name_size</code> characters are copied into the
<code>name</code> array. If the external file name is
longer than <code>name_size</code> with the null terminator, the
return value is not null terminated (similar to <code>strncpy()</code>).
<p>
If <code>name_size</code> is zero or <code>name</code> is the
null pointer, the external file name is not returned.
If <code>offset</code> or <code>size</code> are null pointers
then the corresponding information is not returned.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a dataset creation property list.
<dt><em>int</em> <code>idx</code>
<dd>IN: External file index.
<dt><em>size_t</em> <code>name_size</code>
<dd>IN: Maximum length of <code>name</code> array.
<dt><em>char</em> <code>*name</code>
<dd>OUT: Name of the external file.
<dt><em>off_t</em> <code>*offset</code>
<dd>OUT: Pointer to a location to return an offset value.
<dt><em>hsize_t</em> <code>*size</code>
<dd>OUT: Pointer to a location to return the size of the
external file data.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetDriver">H5Pget_driver</a>
<dt><strong>Signature:</strong>
<dd><em>H5F_driver_t</em> <code>H5Pget_driver</code>(<em>hid_t</em> <code>plist</code>,
)
<dt><strong>Purpose:</strong>
<dd>Returns a low-level file driver identifier.
<dt><strong>Description:</strong>
<dd><code>H5Pget_driver</code> returns the identifier of the
low-level file driver. Valid identifiers are:
<ul>
<li>H5F_LOW_STDIO (0)
<li>H5F_LOW_SEC2 (1)
<li>H5F_LOW_MPIO (2)
<li>H5F_LOW_CORE (3)
<li>H5F_LOW_SPLIT (4)
<li>H5F_LOW_FAMILY (5)
</ul>
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns a low-level driver identifier if successful.
Otherwise returns H5F_LOW_ERROR (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetStdio">H5Pset_stdio</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_stdio</code>(<em>hid_t</em> <code>plist</code>)
<dt><strong>Purpose:</strong>
<dd>Sets the low level file driver to use the functions declared
in the stdio.h.
<dt><strong>Description:</strong>
<dd><code>H5Pset_stdio</code> sets the low level file driver to use
the functions declared
in the stdio.h file: fopen(), fseek() or fseek64(), fread(),
fwrite(), and fclose().
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetStdio">H5Pget_stdio</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pget_stdio</code>(<em>hid_t</em> <code>plist</code>)
<dt><strong>Purpose:</strong>
<dd>Determines whether the file access property list is set to
the stdio driver.
<dt><strong>Description:</strong>
<dd><code>H5Pget_stdio</code> checks to determine whether the
file access property list is set to the stdio driver.
In the future, additional arguments may be added to this
function to match those added to H5Pset_stdio().
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if the file access propety list is set
to the stdio driver.
Otherwise returns FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetSec2">H5Pset_sec2</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_sec2</code>(<em>hid_t</em> <code>plist</code>,
)
<dt><strong>Purpose:</strong>
<dd>Sets the low-level file driver to use the declared functions.
<dt><strong>Description:</strong>
<dd><code>H5Pset_sec2</code> sets the low-level file driver to use
the functions declared
in the unistd.h file: open(), lseek() or lseek64(), read(),
write(), and close().
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetSec2">H5Pget_sec2</a>
<dt><strong>Signature:</strong>
<dd><em>returntype</em> <code>H5Pget_sec2</code>(<em>hid_t</em> <code>plist</code>)
<dt><strong>Purpose:</strong>
<dd>Checks whether the file access propety list is set
to the sec2 driver.
<dt><strong>Description:</strong>
<dd><code>H5Pget_sec2</code> checks to determine whether the
file access property list is set to the sec2 driver.
In the future, additional arguments may be
added to this function to match those added to H5Pset_sec2().
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if the file access propety list is set
to the sec2 driver.
Otherwise returns FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetCore">H5Pset_core</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_core</code>(<em>hid_t</em> <code>plist</code>,
<em>size_t</em> <code>increment</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the low-level file driver to use malloc() and free().
<dt><strong>Description:</strong>
<dd><code>H5Pset_core</code> sets the low-level file driver to use malloc() and free().
This driver is restricted to temporary files which are not
larger than the amount of virtual memory available. The
INCREMENT argument determines the file block size and memory
will be allocated in multiples of INCREMENT bytes. A liberal
INCREMENT results in fewer calls to realloc() and probably
less memory fragmentation.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of a file access property list.
<dt><em>size_t</em> <code>increment</code>
<dd>IN: File block size in bytes.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetCore"></a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pget_core</code>(<em>hid_t</em> <code>plist</code>,
<em>size_t</em> <code>*increment</code>
)
<dt><strong>Purpose:</strong>
<dd>Determines whether the file access property list is set
to the core driver.
<dt><strong>Description:</strong>
<dd><code>H5Pget_core</code> checks to determine whether the
file access property list is set to the core driver.
On success, the block size is returned
through the INCREMENT argument if it isn't the null pointer.
In the future, additional arguments may be added to this
function to match those added to H5Pset_core().
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file access property list.
<dt><em>size_t</em> <code>*increment</code>
<dd>OUT: Pointer to a location to return the file block size (in bytes).
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if the file access propety list is set
to the core driver.
Otherwise returns FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetSplit">H5Pset_split</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_split</code>(<em>hid_t</em> <code>plist</code>,
<em>const char</em> <code>*meta_ext</code>,
<em>hid_t</em> <code>meta_plist</code>,
<em>const char</em> <code>*raw_ext</code>,
<em>hid_t</em> <code>raw_plist</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the low-level driver to split meta data from raw data.
<dt><strong>Description:</strong>
<dd><code>H5Pset_split</code> sets the low-level driver to
split meta data from raw data, storing meta data in one file and
raw data in another file. The meta file will have a name
which is formed by adding <em>meta_extension</em> (recommended
default value: <code>.meta</code>) to the end of the base name
and will be accessed according to the <em>meta_properties</em>.
The raw file will have a name which is formed by appending
<em>raw_extension</em> (recommended default value:
<code>.raw</code>) to the base name and will be accessed according
to the <em>raw_properties</em>.
Additional parameters may be added to this function in the future.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file access property list.
<dt><em>const char</em> <code>*meta_ext</code>
<dd>IN: Name of the extension for the metafile filename.
Recommended default value: <code>.meta</code>.
<dt><em>hid_t</em> <code>meta_plist</code>
<dd>IN: Identifier of the meta file access property list.
<dt><em>const char</em> <code>*raw_ext</code>
<dd>IN: Name extension for the raw file filename.
Recommended default value: <code>.raw</code>.
<dt><em>hid_t</em> <code>raw_plist</code>
<dd>IN: Identifier of the raw file access property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetSplit">H5Pget_split</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pget_split</code>(<em>hid_t</em> <code>plist</code>,
<em>size_t</em> <code>meta_ext_size</code>,
<em>char</em> <code>*meta_ext</code>,
<em>hid_t</em> <code>*meta_properties</code>,
<em>size_t</em> <code>raw_ext_size</code>,
<em>char</em> <code>*raw_ext</code>,
<em>hid_t</em> <code>*raw_properties</code>
)
<dt><strong>Purpose:</strong>
<dd>Determines whether the file access property list is set
to the split driver.
<dt><strong>Description:</strong>
<dd><code>H5Pget_split</code> checks to determine whether the file
access property list is set to the split driver.
On successful return,
<em>meta_properties</em> and <em>raw_properties</em> will
point to copies of the meta and raw access property lists
which should be closed by calling <code>H5Pclose()</code> when
the application is finished with them, but if the meta and/or
raw file has no property list then a negative value is
returned for that property list identifier. Also, if
<em>meta_extension</em> and/or <em>raw_extension</em> are
non-null pointers, at most <em>meta_ext_size</em> or
<em>raw_ext_size</em> characters of the meta or raw file name
extension will be copied to the specified buffer. If the
actual name is longer than what was requested then the result
will not be null terminated (similar to
<code>strncpy()</code>). In the future, additional arguments
may be added to this function to match those added to
<code>H5Pset_split()</code>.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file access property list.
<dt><em>size_t</em> <code>meta_ext_size</code>
<dd>IN: Number of characters of the meta file extension to be
copied to the <code>meta_ext</code> buffer.
<dt><em>OUT</em> <code>*meta_ext</code>
<dd>IN: Meta file extension.
<dt><em>hid_t</em> <code>*meta_properties</code>
<dd>OUT: Pointer to a copy of the meta file access property list.
<dt><em>size_t</em> <code>raw_ext_size</code>
<dd>IN: Number of characters of the raw file extension to be
copied to the <code>raw_ext</code> buffer.
<dt><em>char</em> <code>*raw_ext</code>
<dd>OUT: Raw file extension.
<dt><em>hid_t</em> <code>*raw_properties</code>
<dd>OUT: Pointer to a copy of the raw file access property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if the file access propety list is set
to the split driver.
Otherwise returns FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetFamily">H5Pset_family</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_family</code>(<em>hid_t</em> <code>plist</code>,
<em>hsize_t</em> <code>memb_size</code>,
<em>hid_t</em> <code>memb_plist</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the file access properties list to the <em>family</em>
driver.
<dt><strong>Description:</strong>
<dd><code>H5Pset_family</code> sets the file access properties
to use the <em>family</em>
driver; any previously defined driver properties are erased
from the property list. Each member of the file family will
use <em>member_properties</em> as its file access property
list. The <em>memb_size</em> argument gives the logical size
in bytes of each family member but the actual size could be
smaller depending on whether the file contains holes. The
member size is only used when creating a new file or
truncating an existing file; otherwise the member size comes
from the size of the first member of the family being
opened. Note: if the size of the <code>off_t</code> type is
four bytes then the maximum family member size is usually
2^31-1 because the byte at offset 2,147,483,647 is generally
inaccessable. Additional parameters may be added to this
function in the future.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file access property list.
<dt><em>hsize_t</em> <code>memb_size</code>
<dd>IN: Logical size, in bytes, of each family member.
<dt><em>hid_t</em> <code>memb_plist</code>
<dd>IN: Identifier of the file access property list
for each member of the family.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetFamily">H5Pget_family</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pget_family</code>(<em>hid_t</em> <code>tid</code>,
<em>hsize_t</em> <code>*memb_size</code>,
<em>hid_t</em> <code>*memb_plist</code>
)
<dt><strong>Purpose:</strong>
<dd>Determines whether the file access property list
is set to the family driver.
<dt><strong>Description:</strong>
<dd><code>H5Pget_family</code> checks to determine whether the
file access property list is set to the family driver.
On successful return,
<em>access_properties</em> will point to a copy of the member
access property list which should be closed by calling
<code>H5Pclose()</code> when the application is finished with
it. If <em>memb_size</em> is non-null then it will contain
the logical size in bytes of each family member. In the
future, additional arguments may be added to this function to
match those added to <code>H5Pset_family()</code>.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file access property list.
<dt><em>hsize_t</em> <code>*memb_size</code>
<dd>OUT: Logical size, in bytes, of each family member.
<dt><em>hid_t</em> <code>*memb_plist</code>
<dd>OUT: Identifier of the file access property list
for each member of the family.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if the file access propety list is set
to the family driver.
Otherwise returns FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetCache">H5Pset_cache</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_cache</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>mdc_nelmts</code>,
<em>size_t</em> <code>rdcc_nbytes</code>,
<em>double</em> <code>rdcc_w0</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the number of elements in the meta data cache and the
total number of bytes in the raw data chunk cache.
<dt><strong>Description:</strong>
<dd><code>H5Pset_cache</code> sets the number of elements (objects) in the meta data cache and the
total number of bytes in the raw data chunk cache.
<p>
Sets or queries the meta data cache and raw data chunk cache
parameters. The <em>plist</em> is a file access property
list. The number of elements (objects) in the meta data cache
is <em>mdc_nelmts</em>. The total size of the raw data chunk
cache and the preemption policy is <em>rdcc_nbytes</em> and
<em>w0</em>. For <code>H5Pget_cache()</code> any (or all) of
the pointer arguments may be null pointers.
<p>
The RDCC_W0 value should be between 0 and 1 inclusive and
indicates how much chunks that have been fully read are
favored for preemption. A value of zero means fully read
chunks are treated no differently than other chunks (the
preemption is strictly LRU) while a value of one means fully
read chunks are always preempted before other chunks.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file access property list.
<dt><em>int</em> <code>mdc_nelmts</code>
<dd>IN: Number of elements (objects) in the meta data cache.
<dt><em>size_t</em> <code>rdcc_nbytes</code>
<dd>IN: Total size of the raw data chunk cache, in bytes.
<dt><em>double</em> <code>rdcc_w0</code>
<dd>IN: Preemption policy.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetCache">H5Pget_cache</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pget_cache</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>*mdc_nelmts</code>,
<em>size_t</em> <code>*rdcc_nbytes</code>,
<em>double</em> <code>*rdcc_w0</code>
)
<dt><strong>Purpose:</strong>
<dd>Retrieves maximun sizes of meta data cache and RDCC_WO.
<dt><strong>Description:</strong>
<dd>Retrieves the maximum possible number of elements in the meta
data cache and the maximum possible number of bytes and the
RDCC_W0 value in the raw data chunk cache. Any (or all)
arguments may be null pointers in which case the corresponding
datum is not returned.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier of the file access property list.
<dt><em>int</em> <code>*mdc_nelmts</code>
<dd>IN/OUT: Number of elements (objects) in the meta data cache.
<dt><em>size_t</em> <code>*rdcc_nbytes</code>
<dd>IN/OUT: Total size of the raw data chunk cache, in bytes.
<dt><em>double</em> <code>*rdcc_w0</code>
<dd>IN/OUT: Preemption policy.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetBuffer">H5Pset_buffer</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_buffer</code>(<em>hid_t</em> <code>plist</code>,
<em>size_t</em> <code>size</code>,
<em>void</em> <code>*tconv</code>,
<em>void</em> <code>*bkg</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets type conversion and background buffers.
<dt><strong>Description:</strong>
<dd> Given a dataset transfer property list, <code>H5Pset_buffer</code>
sets the maximum size
for the type conversion buffer and background buffer and
optionally supply pointers to application-allocated buffers.
If the buffer size is smaller than the entire amount of data
being transfered between application and file, and a type
conversion buffer or background buffer is required then
strip mining will be used. However, certain restrictions
apply for the size of buffer which can be used for strip
mining. For instance, when strip mining a 100x200x300
hyperslab of a simple data space the buffer must be large
enough to hold a 1x200x300 slab.
<p>
If TCONV and/or BKG are null pointers then buffers will be
allocated and freed during the data transfer.
<p>
The default value for the maximum buffer is 1 Mb.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset transfer property list.
<dt><em>size_t</em> <code>size</code>
<dd>IN: Size for the type conversion and background buffers.
<dt><em>void</em> <code>tconv</code>
<dd>IN: Pointer to application-allocated type conversion buffer.
<dt><em>void</em> <code>bkg</code>
<dd>IN: Pointer to application-allocated background buffer.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetBuffer">H5Pget_buffer</a>
<dt><strong>Signature:</strong>
<dd><em>size_t</em> <code>H5Pget_buffer</code>(<em>hid_t</em> <code>plist</code>,
<em>void</em> <code>**tconv</code>,
<em>void</em> <code>**bkg</code>
)
<dt><strong>Purpose:</strong>
<dd>Reads buffer settings.
<dt><strong>Description:</strong>
<dd><code>H5Pget_buffer</code> reads values previously set
with H5Pset_buffer().
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset transfer property list.
<dt><em>void</em> <code>**tconv</code>
<dd>OUT: Address of the pointer to application-allocated
type conversion buffer.
<dt><em>void</em> <code>**bkg</code>
<dd>OUT: Address of the pointer to application-allocated
background buffer.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns buffer size if successful;
otherwise 0 on failure.
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetPreserve">H5Pset_preserve</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_preserve</code>(<em>hid_t</em> <code>plist</code>,
<em>hbool_t</em> <code>status</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets the dataset transfer property list status to TRUE or FALSE.
<dt><strong>Description:</strong>
<dd><code>H5Pset_preserve</code> sets the
dataset transfer property list status to TRUE or FALSE.
<p>
When reading or writing compound data types and the
destination is partially initialized and the read/write is
intended to initialize the other members, one must set this
property to TRUE. Otherwise the I/O pipeline treats the
destination datapoints as completely uninitialized.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset transfer property list.
<dt><em>hbool_t</em> <code>status</code>
<dd>IN: Status of for the dataset transfer property list
(TRUE/FALSE).
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetPreserve">H5Pget_preserve</a>
<dt><strong>Signature:</strong>
<dd><em>int</em> <code>H5Pget_preserve</code>(<em>hid_t</em> <code>plist</code>)
<dt><strong>Purpose:</strong>
<dd>Checks status of the dataset transfer property list.
<dt><strong>Description:</strong>
<dd><code>H5Pget_preserve</code> checks the status of the
dataset transfer property list.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset transfer property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns TRUE or FALSE if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetCompression">H5Pset_compression</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_compression</code>(<em>hid_t</em> <code>plist</code>,
<em>H5Z_method_t</em> <code>method</code>,
<em>unsigned int</em> <code>flags</code>,
<em>size_t</em> <code>cd_size</code>,
<em>const void</em> <code>*client_data</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets compression method.
<dt><strong>Description:</strong>
<dd> <code>H5Pset_compression</code> sets the compression method in a dataset creation property
list. This is a catch-all function for defining compresion methods
and is intended to be called from a wrapper such as
<code>H5Pset_deflate()</code>. The dataset creation property
list <em>plist</em> is adjusted to use the specified
compression method. The <em>flags</em> is an 8-bit vector
which is stored in the file as part of the compression message
and passed to the compress and uncompress functions. The
<em>client_data</em> is a byte array of length
<em>cd_size</em> which is copied to the file and passed to the
compress and uncompress methods.
<p>
The FLAGS, CD_SIZE, and CLIENT_DATA are copied to the
property list and eventually to the file and passed to the
compression functions.
<p>
See <a href="Compression.html"><cite>Compression</cite></a>
in the <cite>HDF5 User's Guide</cite> for further information.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset creation property list.
<dt><em>H5Z_method_t</em> <code>method</code>
<dd>IN: Compression method, an integer from 16 to 225.
<dt><em>unsigned int</em> <code>flags</code>
<dd>IN: Compression flags.
<dt><em>size_t</em> <code>cd_size</code>
<dd>IN: Size of the byte array <code>client_data</code>.
<dt><em>const void</em> <code>*client_data</code>
<dd>IN: Client data byte array passed to the compression method.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetCompression">H5Pget_compression</a>
<dt><strong>Signature:</strong>
<dd><em>H5Z_method_t</em> <code>H5Pget_compression</code>(<em>hid_t</em> <code>plist</code>,
<em>unsigned int</em> <code>*flags</code>,
<em>size_t</em> <code>*cd_size</code>,
<em>void</em> <code>*client_data</code>
)
<dt><strong>Purpose:</strong>
<dd>Gets compression method.
<dt><strong>Description:</strong>
<dd><code>H5Pget_compression</code> gets the compression method
information from a dataset creation property list.
The CLIENT_DATA buffer is initially CD_SIZE bytes.
On return, CLIENT_DATA will be initialized
with at most that many bytes, and CD_SIZE will contain the
actual size of the client data, which might be larger than
its original value.<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset creation property list.
<dt><em>unsigned int</em> <code>*flags</code>
<dd>OUT: Compression flags.
<dt><em>size_t</em> <code>*cd_size</code>
<dd>IN/OUT: Size of the <code>client_data</code> array.
<dt><em>void</em> <code>*client_data</code>
<dd>OUT: Byte array for the client data.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns compression method if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-SetDeflate">H5Pset_deflate</a>
<dt><strong>Signature:</strong>
<dd><em>herr_t</em> <code>H5Pset_deflate</code>(<em>hid_t</em> <code>plist</code>,
<em>int</em> <code>level</code>
)
<dt><strong>Purpose:</strong>
<dd>Sets compression method and compression level.
<dt><strong>Description:</strong>
<dd><code>H5Pset_deflate</code> sets the compression method for a
dataset creation property
list to H5D_COMPRESS_DEFLATE and the compression level to
LEVEL which should be a value between zero and nine,
inclusive. Lower compression levels are faster but result in
less compression. This is the same algorithm as used by the
GNU gzip program.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset creation property list.
<dt><em>int</em> <code>level</code>
<dd>IN: Compression level.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns SUCCEED (0) if successful;
otherwise FAIL (-1).
</dl>
<hr>
<dl>
<dt><strong>Name:</strong> <a name="Property-GetDeflate">H5Pget_deflate</a>
<dt><strong>Signature:</strong>
<dd><em>int</em> <code>H5Pget_deflate</code>(<em>hid_t</em> <code>plist</code>
)
<dt><strong>Purpose:</strong>
<dd>Returns the deflate compression level from a dataset creation
property list.
<dt><strong>Description:</strong>
<dd><code>H5Pget_deflate</code> returns the deflate compression level
from a dataset creation property list that uses that method.
<dt><strong>Parameters:</strong>
<dl>
<dt><em>hid_t</em> <code>plist</code>
<dd>IN: Identifier for the dataset creation property list.
</dl>
<dt><strong>Returns:</strong>
<dd>Returns compression level, a value between 0 and 9, if successful.
Otherwise returns FAIL (-1).
</dl>
<hr>
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Last modified: 14 July 1998
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