Base class for all the (U)SAT ETel API parameters.

There may be several versions of a parameter. Parameter classes are named 'name version number', such as RSat::TGetInkeyV1 and RSat::TGetInkeyV2. Both of these classes are used with the "GET INKEY" proactive command. They hold similar information but are designed for use with different versions of the (U)SAT ETel API. Version 2 contains the version 1 class plus extra information. A third version would contain version 2 plus extra information, etc.

In classes derived from RSat::TSatBase, the base class holds the class's version number. The version number is a value from RSat::TSatVersion. Each value in RSat::TSatVersion describes the versions of Symbian OS with which they are used.

You never need to set the version number; the class's constructor does this. Generally, RSat clients do not need to read the version number.

The TSY can use RSat::TSatBase::ExtensionId() to return the version number. A typical situation is this: the TSY is passed a (U)SAT ETel API parameter in a descriptor. The TSY does not know which version it has been given so it should guess. For example, it could unpack the descriptor into the latest version of the parameter then call RSat::TSatBase::ExtensionId() to retrieve the actual version number. If the TSY chose the incorrect version number then the descriptor can be unpacked into the correct parameter class.