diff -r 89d6a7a84779 -r 25a17d01db0c Symbian3/PDK/Source/GUID-C705B0D5-055A-5DAA-9C6E-2FC3519FA50C.dita --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Symbian3/PDK/Source/GUID-C705B0D5-055A-5DAA-9C6E-2FC3519FA50C.dita Fri Jan 22 18:26:19 2010 +0000 @@ -0,0 +1,28 @@ + + + + + +Publish +and Subscribe OverviewThis topic explains the overview of publish and subscribe. +
Purpose

Allows global variables to be set and retrieved, +and allows subscribers to be notified that variables have changed. Note that +you may find such global variables referred to as properties.

+
Architectural relationships

Publish and Subscribe +is implemented on the Kernel side and is accessed from the user side through +the RProperty handle.

+
Description

Publish and Subscribe has three main +components: properties, publishers and subscribers.

Properties

A property is a single data value, that can be either a single 32-bit +value or a variable length set of bytes referred to as a byte array. A byte +array has a maximum size defined by RProperty::KMaxPropertySize.

Publishers

Publishers are threads that define and update a +property.

Subscribers

Subscribers +are threads that listen for changes to a property, and can get the current +value of a property. Typically, a thread gets the value of a property when +notified of changes.

+
\ No newline at end of file