ibm-information-center/dist/eclipse/plugins/i5OS.ic.rzam4_5.4.0.1/rzam4universaldiskformat.htm

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>