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-rw-r--r--doc/html/H5.format.html103
1 files changed, 95 insertions, 8 deletions
diff --git a/doc/html/H5.format.html b/doc/html/H5.format.html
index 59bc28d..afcd444 100644
--- a/doc/html/H5.format.html
+++ b/doc/html/H5.format.html
@@ -266,7 +266,7 @@ each high-level object.
</tr>
<tr align=center>
- <td colspan=4>Reserved Address</td>
+ <td colspan=4>Driver Information Block Address</td>
</tr>
<tr align=center>
@@ -480,12 +480,14 @@ each high-level object.
used.</td>
</tr>
- <tr valign=top>
- <td>Reserved Address</td>
- <td>This address field is present for alignment purposes and
- is always set to the undefined address value (all bits
- set).</td>
- </tr>
+ <tr valign=top>
+ <td>Driver Information Block Address</td>
+ <td>This is the relative file address of the file driver
+ information block which contains driver-specific
+ information needed to reopen the file. If there is no
+ driver information block then this entry should be the
+ undefined address (all bits set).</td>
+ </tr>
<tr valign=top>
<td>Root Group Symbol Table Entry</td>
@@ -497,6 +499,91 @@ each high-level object.
</table>
</center>
+ <p>The file driver information block is an optional region of the
+ file which contains information needed by the file driver in
+ order to reopen a file. The format of the driver information
+ block is:
+
+ <p>
+ <center>
+ <table border align=center cellpadding=4 width="80%">
+ <caption align=top>
+ <B>Driver Information Block</B>
+ </caption>
+
+ <tr align=center>
+ <th width="25%">byte</th>
+ <th width="25%">byte</th>
+ <th width="25%">byte</th>
+ <th width="25%">byte</th>
+ </tr>
+
+ <tr align=center>
+ <td>Version</td>
+ <td colspan=3>Reserved (zero)</td>
+ </tr>
+
+ <tr align=center>
+ <td colspan=4>Driver Information Size (4 bytes)</td>
+ </tr>
+
+ <tr align=center>
+ <td colspan=4><br>Driver Identification (8 bytes)<br><br></td>
+ </tr>
+
+ <tr align=center>
+ <td colspan=4><br><br>Driver Information<br><br><br></td>
+ </tr>
+ </table>
+ </center>
+
+ <p>
+ <center>
+ <table align=center width="80%">
+ <tr>
+ <th width="30%">Field Name</th>
+ <th width="70%">Description</th>
+ </tr>
+
+ <tr valign=top>
+ <td>Version</td>
+ <td>The version number of the driver information block. The
+ file format documented here is version zero.</td>
+ </tr>
+
+ <tr valign=top>
+ <td>Driver Information Size</td>
+ <td>The size in bytes of the Driver Information part of this
+ structure.</td>
+ </tr>
+
+ <tr valign=top>
+ <td>Driver Identification</td>
+ <td>This is an eight-byte ASCII string without null
+ termination which identifies the driver and version number
+ of the Driver Information block. The predefined drivers
+ supplied with the HDF5 library are identified by the
+ letters "NCSA" followed by the first four characters of
+ the driver name. If the Driver Information block is not
+ the original version then the last letter(s) of the
+ identification will be replaced by a version number in
+ ASCII. For example, the various versions of the "family"
+ driver will be identified by "NCSAfami", "NCSAfam0",
+ NCSAfam1", etc. Identification for user-defined drivers is
+ arbitrary but should be unique.</td>
+ </tr>
+
+ <tr valign=top>
+ <td>Driver Information</td>
+ <td>Driver information is stored in a format defined by the
+ file driver and encoded/decoded by the driver callbacks
+ invoked from the <code>H5FD_sb_encode</code> and
+ <code>H5FD_sb_decode</code> functions.</td>
+ </tr>
+ </table>
+ </center>
+
+
<h3><a name="Btrees">Disk Format: Level 1A - B-link Trees</a></h3>
<p>B-link trees allow flexible storage for objects which tend to grow
@@ -3584,7 +3671,7 @@ data-type.
<address><a href="mailto:koziol@ncsa.uiuc.edu">Quincey Koziol</a></address>
<address><a href="mailto:matzke@llnl.gov">Robb Matzke</a></address>
<!-- hhmts start -->
-Last modified: Fri Jun 11 14:11:57 EDT 1999
+Last modified: Tue Aug 17 10:57:50 EDT 1999
<!-- hhmts end -->
</body>
</html>