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<concept id="GUID-26DBE128-6244-557E-989D-A4A608F43A0F" xml:lang="en"><title>System

State Manager Overview</title><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>The System State Manager (SSM) component controls transitioning of the

device to different system states, and reacts to changes made to the System-wide

Properties. </p>

<section><title>Required background</title> <p>You must have an understanding

on Generic Start-up Architecture before using System State Manager. </p> </section>

<section><title>Key concepts</title> <dl>

<dlentry>

<dt>Generic Start-up Architecture (GSA)</dt>

<dd><p>This architecture allows easy customization of the device’s (mobile)

start-up to provide improved device performance. The main components within

the Generic Start-up Architecture are Base Starter (EStart) and AMA Starter. </p> </dd>

</dlentry>

<dlentry>

<dt> SSM</dt>

<dd><p>This is a component of SSMA that controls transitioning of the device

(mobile) to different system states, and reacts to changes of the system-wide

properties. </p> </dd>

</dlentry>

<dlentry>

<dt>System state </dt>

<dd><p>This indicates the state of the device (mobile). It is controlled by

a state machine that is SSM. These states are defined by system state policies

within a SSM plug-in and system state changes are triggered by system-wide

property changes or external requests. </p> </dd>

</dlentry>

<dlentry>

<dt> System-wide Property</dt>

<dd><p>This allows components to be aware of the system-state. They are defined

by system-wide property policies within a SSM plug-in that can be customised

by licensees. Custom commands are plug-in dlls implementing the <codeph>MSsmCustomCommand</codeph> interface

in SSM. Using custom command licensees can develop alternative devices for

performing the functionality implemented in a command. </p> </dd>

</dlentry>

<dlentry>

<dt> Custom Command</dt>

<dd><p>Custom commands are plug-in dlls implementing the <codeph>MSsmCustomCommand</codeph> interface

in SSM. Using custom command licensees can develop alternative devices for

performing the functionality implemented in a command. </p> </dd>

</dlentry>

</dl> </section>

<section><title>API summary</title> <table id="GUID-57F2026E-7F39-5B93-8E87-51CCB4DAF0A7">

<tgroup cols="2"><colspec colname="col0"/><colspec colname="col1"/>

<thead>

<row>

<entry>API names </entry>

<entry>Description</entry>

</row>

</thead>

<tbody>

<row>

<entry><p> <xref href="GUID-8CE82869-EA9E-327C-B817-ACF497CCDC9D.dita"><apiname>RSsmStateManager</apiname></xref>  </p> </entry>

<entry><p>A System State Management control class, which can be used to request

for a change in the system state or the system-wide property. </p> </entry>

</row>

<row>

<entry><p> <xref href="GUID-89C25B0F-DB76-30D5-A4D6-0C12922194E4.dita"><apiname>RSsmStateAwareSession</apiname></xref>  </p> </entry>

<entry><p>A system-state aware component, which can be used to provide APIs

for components that want to be system state aware. </p> </entry>

</row>

<row>

<entry><p> <xref href="GUID-FE828A1B-B117-39AD-B20D-FF2CC8A4EEE4.dita"><apiname>RSsmSystemWideProperty</apiname></xref>  </p> </entry>

<entry><p>A system-wide property class, which can also be used to provide

an API for components that want to be notified of changes to a particular

system-wide property. </p> </entry>

</row>

</tbody>

</tgroup>

</table> </section>

<section><title>Typical uses</title> <p><b>Creating a custom command</b> </p> <p>Custom

commands are plug-in dlls implementing the <xref href="GUID-DEDD8780-C422-3239-ACDC-A66D209992E6.dita"><apiname>MSsmCustomCommand</apiname></xref> interface

in SSM. Using custom command licensees can develop alternative devices for

performing the functionality implemented in a command. </p> <p>For more information

about creating and running a custom command, see <xref href="GUID-EFBBB53F-8402-5010-8B8D-96D0FC46F784.dita">Creating

a Custom Command</xref> and <xref href="GUID-63F2124B-9B41-58D8-9439-CE4D8C3503D8.dita">Running

a custom command</xref>. </p> <p><b>Making components to be system state aware</b> </p> <p>A

system state aware component is notified of the changes taking place within

SSMA through, <xref href="GUID-89C25B0F-DB76-30D5-A4D6-0C12922194E4.dita"><apiname>RSsmStateAwareSession</apiname></xref>. A user must make a

component to be state aware because SSM must perform certain defined actions

based on the state changes. For more information about making a component

to be aware of its state, see <xref href="GUID-FEA8BB25-3F1F-5F2E-92E3-E5CF360BDD4B.dita">Making

a State Aware Component</xref>. </p> <p><b>Monitoring a system-wide property</b> </p> <p>System-wide

properties allow components to be aware about the state of the device. If

there is any change in the system-wide property value, SSM sends the notification

messages to the requested components. For more information about monitoring

a system-wide property, see <xref href="GUID-F892D93D-0B59-592A-9DA5-AD4243F607E3.dita">Monitoring

a System-Wide Property</xref>. </p> <p><b>Creating a Static CommandList</b> </p> <p>Static

commandList (SCL) provides information about the commands that must be run

at startup. For more information about creating a SCL, see <xref href="GUID-E9FAE433-BDBE-5ABD-B168-6562D29112B1.dita">Creating

a Static commandList</xref>. </p> <p><b>Running a conditional command in a

CommandList</b> </p> <p>When loading a commandList, the resource file reader

makes a decision based upon the value of the <codeph>conditional_information</codeph>.

By default, its value is zero and the commands are unconditional. For more

information about running a conditional command in a commandList, see <xref href="GUID-C01412C2-ED4E-501C-8E79-F0293936845A.dita">Running a Command Conditionally

in a commandList</xref>. </p> </section>

</conbody></concept>