Conventions used in the call descriptions

For each call, this collection of topics gives a description of the parameters and usage of the call in a format that is independent of programming language. This is followed by typical invocations of the call, and typical declarations of its parameters, in each of the supported programming languages.

Important: When coding IBM MQ API calls we must ensure that all relevant parameters (as described in the following sections) are provided. Failure to do so can produce unpredictable results. The description of each call contains the following sections:

    Call name
    The call name, followed by a brief description of the purpose of the call.

    Parameters
    For each parameter, the name is followed by its data type in parentheses ( ) and one of the following:

      input
      You supply information in the parameter when you make the call.

      output
      The queue manager returns information in the parameter when the call completes or fails.

      input/output
      You supply information in the parameter when you make the call, and the queue manager changes the information when the call completes or fails.

    For example: Compcode (MQLONG) - output
    In some cases, the data type is a structure. In all cases, there is more information about the data type or structure in Elementary data types.

    The last two parameters in each call are a completion code and a reason code. The completion code indicates whether the call completed successfully, partially, or not at all. Further information about the partial success or the failure of the call is given in the reason code. For more information about each completion and reason code, see Return codes.

    Usage notes
    Additional information about the call, describing how to use it and any restrictions on its use.

    Assembler language invocation
    Typical invocation of the call, and declaration of its parameters, in assembler language.

    C invocation
    Typical invocation of the call, and declaration of its parameters, in C.

    COBOL invocation
    Typical invocation of the call, and declaration of its parameters, in COBOL.

    PL/I invocation
    Typical invocation of the call, and declaration of its parameters, in PL/I.

    All parameters are passed by reference.

    Visual Basic invocation
    Typical invocation of the call, and declaration of its parameters, in Visual Basic.

Other notation conventions are:

    Constants
    Names of constants are shown in uppercase; for example, MQOO_OUTPUT. A set of constants having the same prefix is shown as follows: MQIA_*. See Constants for the value of a constant.

    Arrays
    In some calls, parameters are arrays of character strings that do not have fixed sizes. In the descriptions of these parameters, a lowercase n represents a numeric constant. When you code the declaration for that parameter, replace the n with the numeric value that you require.

Parent topic: Call descriptions