LIBRARY resources

Use the LIBRARY resource to define the physical and operational characteristics of a dynamic program LIBRARY concatenation.

The LIBRARY definition includes attributes that provide the name of the data set, or sets, within the LIBRARY resource and other details about the operational status of the LIBRARY.

DFHRPL is a special example of a LIBRARY which cannot be altered in a running CICS® system, and does not appear as a resource in CEDA.

Data sets in a dynamic program LIBRARY concatenation can reside in the extended addressing space (EAS) of an extended address volume (EAV) DASD volume.

There is no 'group commit' for LIBRARY resources. Each LIBRARY in a CSD group is committed separately when the group is installed. To achieve an effect similar to group install, you can use the Disabled status to install a set of LIBRARY resources which would then be SET to an Enablestatus of Enabled when all resources are installed.

LIBRARY resources in CICS bundles

You can use a CICS bundle to create, edit, and install a LIBRARY resource definition. If you create a LIBRARY resource in this way, you must use the CICS bundle to manage the lifecycle of that resource, and you cannot manage the resource independently. You can inquire on a LIBRARY resource that is dynamically generated by a CICS bundle, by using the EXEC CICS INQUIRE LIBRARY or CEMT INQUIRE LIBRARY command. However, you cannot issue SET or DISCARD commands against a LIBRARY resource that is dynamically generated by a CICS bundle. You must issue the commands against the BUNDLE resource, and CICS applies them to the LIBRARY resource.

If a program is loaded from a LIBRARY concatenation that was defined and installed by a CICS bundle, that program is treated as though it was defined in the CICS bundle, even though the program might have been defined independently. The lifecycle of these programs conforms to the lifecycle of the CICS bundle in which the LIBRARY resource is defined. If a CICS bundle that contains a LIBRARY resource is disabled, all programs loaded from that LIBRARY concatenation are disabled.

For more information about defining resources in CICS bundles, see Defining CICS bundles.

Private LIBRARY resources for applications

For supported resource types, a CICS resource is private if the resource is defined in a CICS bundle that is packaged and installed as part of an application, either as part of the application bundle, or as part of the application binding. When you create a CICS resource in this way, the resource is not available to any other application or version installed on the platform, and it is not available to other applications in the CICS region. It can be used only by the version of the application where the resource is defined. These resources are known as private resources.

The LIBRARY resource is supported as a private resource for an application version. Each version of an application should include a private LIBRARY resource that represents a version-specific data set containing the load modules for the application.

  • When a task for an application deployed on a platform requires a program load, the private LIBRARY concatenations defined for that version of the application are searched first, so that the correct version of the program is loaded. If multiple LIBRARY concatenations are defined for the same application version, they are searched in order of their ranking.
  • If there are no LIBRARY concatenations defined in the application, or the program is not found in any of the private LIBRARY concatenations, the public LIBRARY concatenations defined for the whole CICS region (including DFHRPL) are searched.
  • For a task that is not associated with an application deployed on a platform, only the public LIBRARY concatenations are searched, so all program load modules that are resident in private LIBRARY concatenations are not available.

For a private LIBRARY resource that is defined in a CICS bundle that is packaged and installed as part of an application bundle or application binding bundle, the name of the LIBRARY resource is not used as the DD name for the LIBRARY concatenation of data sets. Instead, CICS requests a unique DD name for the LIBRARY concatenation of data sets when the application is installed on the platform. The resource name can therefore be the same as LIBRARY names used elsewhere in the installation, or by different versions of the application. CICS issues message DFHLD0518 to state the DD name that z/OS® has generated for the LIBRARY concatenation. You can also view the data set names for an installed application in the CICS Explorer®.

For more information about private resources, see Characteristics of bundled resources.