Symbian3/PDK/Source/GUID-BBC49BE2-5147-5988-93FD-9CECF90BB223.dita
author Dominic Pinkman <Dominic.Pinkman@Nokia.com>
Tue, 30 Mar 2010 11:56:28 +0100
changeset 5 f345bda72bc4
parent 3 46218c8b8afa
child 14 578be2adaf3e
permissions -rw-r--r--
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
5
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     1
<?xml version="1.0" encoding="utf-8"?>
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     2
<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     3
<!-- This component and the accompanying materials are made available under the terms of the License 
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     4
"Eclipse Public License v1.0" which accompanies this distribution, 
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     5
and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     6
<!-- Initial Contributors:
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     7
    Nokia Corporation - initial contribution.
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     8
Contributors: 
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
     9
-->
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
    10
<!DOCTYPE concept
f345bda72bc4 Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents: 3
diff changeset
    11
  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
1
25a17d01db0c Addition of the PDK content and example code for Documentation_content according to Feature bug 1607 and bug 1608
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
diff changeset
    12
<concept xml:lang="en" id="GUID-BBC49BE2-5147-5988-93FD-9CECF90BB223"><title>Memory Management</title><prolog><metadata><keywords/></metadata></prolog><conbody><p>The P.I.P.S. System Call Adaptation Layer (SCAL) known as <i>Backend</i> uses its own private heap for storing objects in memory. </p> <p>By using a private heap, </p> <ul><li id="GUID-5EBDFF66-316F-56CC-8F19-B684B904A6BF"><p>the SCAL retains complete control over usage of the heap </p> </li> <li id="GUID-83256AD7-A1C3-5A4C-A558-00F7FF012AC8"><p>system wide resources are not allocated within the context of users' private and thread owned heaps </p> </li> <li id="GUID-65F6AA57-E8E5-5FA3-810A-0C489E931054"><p>the SCAL is virtually out-of-memory protected; that is, if the client application exhausts its own heap, most P.I.P.S. APIs will continue to function correctly, for example, opening or closing file descriptors </p> </li> <li id="GUID-810D513C-77ED-538F-A2EE-F9668DBA523E"><p>there is no need for application <codeph>EXE</codeph> s to explicitly clean up memory used by the SCAL prior to thread or process termination (this would be necessary to prevent <codeph>UHEAP</codeph> macros from panicking). The explicit calling of cleanup APIs is especially unintuitive for open-source applications and it is not obvious when a native Symbian platform <codeph>EXE</codeph> is using a <codeph>STDDLL</codeph>. </p> </li> </ul> <p>The use of a private heap might not make P.I.P.S. very memory efficient but it makes it much more intuitive to the user and memory safe. </p> <section><title>Limitations</title> <p>During low memory conditions, your P.I.P.S. application may crash at launch with an <codeph>STDLIBS-INIT</codeph> panic. This indicates that the P.I.P.S. subsystem was unable to initialise its core components and cannot function. Hybrid applications may also encounter this panic, for the same reasons, when it invokes a P.I.P.S. API. </p> </section> </conbody></concept>