A prerequisite adds a requirement that the order of installation be controlled. The prerequisite fileset must be installed before the requesting fileset. This implies that some content of the prerequisite is used or modified during the installation process.

Advanced topic: determining corequisite and prerequisite filesets with the swlist command

You can use the following command to determine the dependent filesets. Replace dependency_type with either corequisite or prerequisite, as appropriate.

swlist -vl fileset -a dependency_type fileset

For example:

$ swlist -vl fileset -a corequisite PHSS_29964.DCEC-ENG-A-MAN

#Initializing...

#Contacting target "some_system"...

#PHSS_29964.DCEC-ENG-A-MAN fileset

corequisites PHCO_24400.CORE-SHLIBS,fa=HP-UX_B.11.11_32/64

Enforced and unenforced (manual) dependencies

A patch's dependency upon another patch will either be enforced or unenforced by SD-UX. Starting with HP-UX 11i v1 (B.11.11), SD-UX install commands supported the use of requisites for automatically enforcing dependencies. Prior to HP-UX 11i v1, users had to maintain dependencies manually.

•Enforced dependencies

Dependencies that are registered using corequisite or prerequisite attributes and managed by SD-UX.

•Unenforced dependencies (also known as manual dependencies)

Dependencies that SD-UX does not register as requisites and thus cannot enforce when performing patch installation. You can identify these types of dependencies by checking the manual_dependency category tag. The user must ensure that the required patches are installed to satisfy these manual dependencies.

Impact of dependencies on acquiring patches

HP strongly recommends that you use the ITRC as your primary source for acquiring patches. If you acquire individual patches using the ITRC's Patch Database, the patches required to meet the dependencies of these patches are automatically selected for download along with the patches you selected manually. The analysis performed by the Patch Database to select these patches takes into account supersession and patch warnings. Unless you have a specific reason to do otherwise, you should download these automatically selected patches along with the patches you explicitly selected. This automatic selection of patches represents one of the many time saving features provided by the ITRC.

For a description of how to identify and acquire the additional patches that might be needed to satisfy dependencies, see “Advanced topic: checking for all patch dependencies” (page 59).

NOTE: If you download patches from sources other than the ITRC, you are completely responsible for identifying and downloading the patches required to satisfy all dependencies.

Standard HP-UX patch bundles, such as the Quality Pack, do not require users to perform any dependency analysis. All patches required to satisfy all dependencies are included in the bundles. Using standard HP-UX patch bundles increases confidence that you have obtained and installed all necessary patches to satisfy all dependencies.

32 HP-UX patch overview