API parameters

After you decide which API to use, you need to code a call to the API and pass to the API the set of parameters that are appropriate for it.

There are three types of parameters:

• Required: All of the parameters are in the specified order.
• Optional: All or none of the parameters are within the optional group. You must either include or exclude the entire group. You cannot use only one of these parameters. In addition, you must include all preceding parameters.
• Omissible: The parameters can be omitted. When these parameters are omitted, you must pass a null pointer.

For program-based and service-program-based APIs, the values for all parameters that identify objects on the system must be in *NAME (basic name) format, left-aligned, uppercase, and with valid special characters. (The *NAME format is a character string that must begin with an alphabetic character (A through Z, $, #, or @) followed by up to 9 characters (A through Z, 0 through 9, $, #, @, ), or _). The system uses an object name as is; it does not change or check the object name before locating the object. This can improve the performance of the API. An incorrect name usually causes an Object not found error.