75 lines
5.6 KiB
HTML
75 lines
5.6 KiB
HTML
|
<?xml version="1.0" encoding="UTF-8"?>
|
||
|
|
<!DOCTYPE html
|
||
|
|
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
||
|
|
<html lang="en-us" xml:lang="en-us">
|
||
|
|
<head>
|
||
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
||
|
|
<meta name="security" content="public" />
|
||
|
|
<meta name="Robots" content="index,follow" />
|
||
|
|
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
|
||
|
|
<meta name="DC.Type" content="concept" />
|
||
|
|
<meta name="DC.Title" content="Universal disk format" />
|
||
|
|
<meta name="abstract" content="UDF (Universal Disk Format) is the OSTA (Optical Storage Technology Association) supported subset of ISO/IEC 13346." />
|
||
|
|
<meta name="description" content="UDF (Universal Disk Format) is the OSTA (Optical Storage Technology Association) supported subset of ISO/IEC 13346." />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzam4optmedfrmat.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzam4udfvoldirfile.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzam4udfproginterfces.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzam4udfdirfiilesec.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzam4udfmediainterchg.htm" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="rzam4udfdirstructperf.htm" />
|
||
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 2004, 2006" />
|
||
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 2004, 2006" />
|
||
|
|
<meta name="DC.Format" content="XHTML" />
|
||
|
|
<meta name="DC.Identifier" content="universaldiskformat" />
|
||
|
|
<meta name="DC.Language" content="en-us" />
|
||
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
||
|
|
<!-- US Government Users Restricted Rights -->
|
||
|
|
<!-- Use, duplication or disclosure restricted by -->
|
||
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
||
|
|
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
|
||
|
|
<link rel="stylesheet" type="text/css" href="./ic.css" />
|
||
|
|
<title>Universal disk format</title>
|
||
|
|
</head>
|
||
|
|
<body id="universaldiskformat"><a name="universaldiskformat"><!-- --></a>
|
||
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
||
|
|
<h1 class="topictitle1">Universal disk format</h1>
|
||
|
|
<div><p>UDF (Universal Disk Format) is the OSTA (Optical Storage Technology
|
||
|
|
Association) supported subset of ISO/IEC 13346.</p>
|
||
|
|
<div class="p"> UDF also addresses ECMA-167 which is equivalent to ISO 13346. UDF is a
|
||
|
|
writable file format that provides true space reclaim capabilities as well
|
||
|
|
as file and directory level security. This section contains detailed information
|
||
|
|
on the i5/OS™ implementation
|
||
|
|
of UDF for direct-attached (C4x) 3995 optical media libraries as well as a
|
||
|
|
DVD-RAM device.<div class="note"><span class="notetitle">Note:</span> Although not accessible through i5/OS, CD and DVD media that are created
|
||
|
|
using the supplementary volume descriptor of ISO 9660 may be accessible in
|
||
|
|
an iSeries™ server.
|
||
|
|
You can access them through an integrated server. For more information, see
|
||
|
|
the <em>Windows<sup>®</sup> environment on iSeries</em> and <em>Linux<sup>®</sup> on an Integrated xSeries<sup>®</sup> Solution</em> topics.</div>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
<div>
|
||
|
|
<ul class="ullinks">
|
||
|
|
<li class="ulchildlink"><strong><a href="rzam4udfvoldirfile.htm">Volume, directory, and file names</a></strong><br />
|
||
|
|
Volume identifiers can be a maximum of 30 characters and must contain only alphabetic characters (A through Z), numeric characters (0 through 9), a hyphen (-), or a period (.). The first character must be alphabetic or numeric, and the identifier cannot contain imbedded blanks.</li>
|
||
|
|
<li class="ulchildlink"><strong><a href="rzam4udfproginterfces.htm">Programming interfaces UDF</a></strong><br />
|
||
|
|
You can create files or read files on UDF media by using either
|
||
|
|
the Hierarchical File System (HFS) application programming interface (API)
|
||
|
|
or the integrated file system programming interface. There are things specific
|
||
|
|
to the i5/OS implementation
|
||
|
|
of the UDF media format that application developers need to know.</li>
|
||
|
|
<li class="ulchildlink"><strong><a href="rzam4udfdirfiilesec.htm">Directory and file security</a></strong><br />
|
||
|
|
Directory and file-level security is available for UDF volumes. The system maintains the data authorities of optical directories and files for three groups of users; owner, group, and public. Volume level security is also available through authorization lists.</li>
|
||
|
|
<li class="ulchildlink"><strong><a href="rzam4udfmediainterchg.htm">Media interchange</a></strong><br />
|
||
|
|
UDF media created on i5/OS is UDF Version 2.01. This media will
|
||
|
|
interchange to other operating system platforms that support this version
|
||
|
|
of UDF.</li>
|
||
|
|
<li class="ulchildlink"><strong><a href="rzam4udfdirstructperf.htm">Directory structure and performance UDF</a></strong><br />
|
||
|
|
UDF volumes have a single (hierarchical) directory structure to access files. Because of this hierarchical directory structure, the depth of a directory tree has a direct impact on file performance. For example, if /DIRECTORY1 contains 1000 files and /DIRECTORY2 contains 100 files, file search times for files in /DIRECTORY1, in general, take longer than file searches in /DIRECTORY2. This is because the system performs file searches hierarchically, which may require looking at every entry in the directory.</li>
|
||
|
|
</ul>
|
||
|
|
|
||
|
|
<div class="familylinks">
|
||
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzam4optmedfrmat.htm" title="i5/OS provides support for several optical media types and media formats.">Optical media formats</a></div>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
</body>
|
||
|
|
</html>
|