To use window services, you issue CALLs that invoke the appropriate window services program. Each service program performs one or more functions and requires a set of parameters coded in a specific order on the CALL statement.

Depending on the function requested from a service, there might be one or more parameter values that the service ignores. Although a service might ignore a parameter value, you must still code that parameter on the CALL statement. Because the service ignores the parameter value, you can assign the parameter any value that is acceptable for the parameter’s data type. If the service uses a particular parameter value, the CALL statement description in this topic defines the allowable values that you can assign to the parameter.

This topic describes the CALL statements that invoke window services. Each description includes a syntax diagram, parameter descriptions, and return code and reason code explanations with recommended actions. Return codes and reason codes are shown in hexadecimal followed by the decimal equivalent enclosed in parentheses. For examples of how to code the CALL statements, see Window services coding examples.