Login and session information

Almost every  C API function has a control parameter as its first input argument. This parameter contains the login and session information required to connect to an  and, thus, required for almost every operation.

The control parameter was optional in  version 3.x and earlier. Therefore, you must add the control parameter to recompiled pre-4.x API programs if you use these programs with later versions of the  API.

The control parameter is a pointer to an ARControlStruct structure (see the following figure).

Structure used to provide required login information 


This structure has the following elements:

 Nearly all function calls require the login and session information that ARControlStruct contains (stored in both single- and multiple-server environments) because the API does not always maintain a server connection between calls.

When a program calls ARInitialization at the beginning of its execution, the  C API returns the data in a ARControlStruct. This is the structure that the program passes as an input parameter in subsequent API calls.