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<concept id="GUID-B5BA3CB6-F2B8-524B-BF99-545AAE81549A" xml:lang="en"><title>Message

Stores</title><shortdesc>The SMS stack uses the following stores to store a complete message. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<section id="GUID-0754BD99-4FFF-5AC2-8E33-7E3B897C03D0"><title>Segmentation

and reassembly (SAR) stores</title> <p>The SMS messages are sent as PDUs and

all the PDUs are required to display the message to the user. The PDUs should

be stored until all the PDUs are received by the device. The SMS stack stores

the incomplete message PDUs in message stores for persistence storage. The

segmentation store and the reassembly store are both created by the GSMU DLL.

The message stores are also used to store the WAP datagrams. </p> <p> <xref href="GUID-B9382772-FC6F-3A90-AF3B-218A299D64C3.dita"><apiname>TSAREntry</apiname></xref> provides

information that is useful for the clients to segment and reassemble the SMS

messages and WAP datagrams. TSAREntry provides information about the reference,

total number of parts and the index of the parts of the complete message or

datagram. </p> <p> <xref href="GUID-B9382772-FC6F-3A90-AF3B-218A299D64C3.dita"><apiname>TSAREntry</apiname></xref> class also provides get and

set methods for four non generic data items in a message. </p> <p>The <xref href="GUID-349FD476-1D50-3D6A-8023-7CBB7DE4821F.dita"><apiname>CSARStore</apiname></xref> provides

the methods to create the SAR stores and store the information useful for

segmentation and reassembly. The <xref href="GUID-349FD476-1D50-3D6A-8023-7CBB7DE4821F.dita"><apiname>CSARStore</apiname></xref> contains a permanent

store and a list of <xref href="GUID-B9382772-FC6F-3A90-AF3B-218A299D64C3.dita"><apiname>TSAREntry</apiname></xref> elements. The member functions

of the <xref href="GUID-349FD476-1D50-3D6A-8023-7CBB7DE4821F.dita"><apiname>CSARStore</apiname></xref> allow the client applications to create

a new store, add an entry, update an entry and delete the store. </p> </section>

<section id="GUID-860AC34F-AD6A-5F01-86E9-B76DE3F9ADF3"><title>Segmentation

store</title> <p>The <xref href="GUID-349FD476-1D50-3D6A-8023-7CBB7DE4821F.dita"><apiname>CSARStore</apiname></xref> creates the segmentation

store as <codeph>smssegst.dat</codeph>. The SMS message is split into individual

PDUs before sending them to the network. The segmentation store is used to

store the PDUs. The segmentation store enables the client applications to

receive the status report of the PDUs. </p> <p><b>Segmentation store data </b> </p> <p>The clients can implement segmentation

store using <xref href="GUID-7907447F-BFAC-3916-AEC0-90AD5DF426DD.dita"><apiname>CSmsSegmentationStore</apiname></xref> class. <xref href="GUID-07379C99-2BE4-316F-8CE1-5AFB9C0AA23C.dita"><apiname>CSegmentationStore</apiname></xref> is

derived from <xref href="GUID-349FD476-1D50-3D6A-8023-7CBB7DE4821F.dita"><apiname>CSARStore</apiname></xref>. The segmentation store is generally

used to store <codeph>SUBMIT</codeph> and <codeph>COMMAND</codeph> PDUs. The

PDUs are stored as additional stream ID in the store. Each stream ID contains

the SMS address, SMS message and an array of status reference items. The segmentation

store creates a log of all sent and unsent PDUs with a log ID. The SMS stack

uses the log ID to resend the message PDUs which failed. </p> </section>

<section id="GUID-C48FFB78-1C80-5ECE-A19F-DE98A1814C25"><title>Reassembly

store</title> <p>The <xref href="GUID-349FD476-1D50-3D6A-8023-7CBB7DE4821F.dita"><apiname>CSARStore</apiname></xref> class creates the reassembly

store as <codeph>smsreast.dat</codeph> . The reassembly store is used to individual

PDUs when received from the network. Once all the PDUs of a message are received

they are reassembled by the SMS stack. A complete message is then created,

the message is ready for the client applications. </p> <p><b>Reassembly store data </b> </p> <p>The clients can implement the reassembly

store using <xref href="GUID-1100B8E0-0006-35B4-B15C-989F3B0030B6.dita"><apiname>CSmsReassemblyStore</apiname></xref> class. The <xref href="GUID-E4E30D66-BCD0-3002-9A02-6B3EF7BF39A4.dita"><apiname>CSmsReassembly</apiname></xref> class

is derived from CSARStore. The <xref href="GUID-1100B8E0-0006-35B4-B15C-989F3B0030B6.dita"><apiname>CSmsReassemblyStore</apiname></xref> class

provides methods that can be used by the client applications to search for

a PDU, update a existing PDU, clear the store and compact the store. </p> </section>

<section id="GUID-C641C3FE-43B8-52CA-936A-5B3741C99894"><title>Class 0 reassembly

store</title> <p>The normal SMS store are not designed to handle Class 0 SMS.

A new class 0 reassembly store is available to handle the class 0 SMS messages

in out of disk conditions. The class 0 reassembly store contains two stores

1) A permanent file store and 2) Pre-allocated file store. The pre allocated

file store is reserved exclusively for the class 0 SMS. The pre-allocated

file store can be <xref href="GUID-266B3FD6-A414-599D-BF31-FF67ADDD4E70.dita">configured</xref> to

reserve for pre-defined number of PDUs. The pre-allocated store can only be

configured by the licensees of Symbian platform. In normal conditions the

message PDUs are stored in the permanent file store. In out of disk conditions

it is not possible to delete older PDUs in the permanent files store. The

SMS stack uses the pre-allocated store during the out of disk conditions.

When the number of PDUs exceed the specified level in the ESK file, the SMS

stack deleted the older PDUs to clear up space for the new incoming PDUs.

The pre-allocated file store cannot be used to store other class/ type of

SMS messages. <xref href="GUID-F701D74D-6BC8-337C-AF36-971CDD8E5F7D.dita"><apiname>CClass0SmsReassemblyStore</apiname></xref> store provides

the required methods for the clients to use the class 0 reassembly store.

The class 0 reassembly store provides the same functionality as the reassembly

store. The additional functionality is that the client applications are able

to process an incomplete message and display it to the users. </p> </section>