The arguments are the actual data the operation on a connectivity transfers, i.e. the “what”. Typically and most importantly, arguments contain the data value being read or written or obtained through subscription.

As with the parameters, they usually depend on the type of point, and the operation involved.

Arguments are represented by an object that has properties, divided into several categories. The categories are as follows:

• Input: The data that is taken from the target and provided to the operation (for example, a value to be written).
• Output: The data that is obtained by the operation and stored into the target (for example, the value read).
• Input/Output: A combination of an input and an output argument.
• Result: The result of the operation (for example, the error ID returned).

There is an important distinction between the outputs, and the results. Each operation can be either successful, or not. When the operation completes, the result arguments are always available. The outputs, however, are only available when the operation succeeded.