Application Packaging Developer's Guide

Chapter 1 Designing a Package

Before you build a package, you need to know which files you need to create and the commands you need to execute. You also need to consider your application software's requirements, and the needs of your customer—the administrators who will be installing your package. This chapter discusses the files, commands, and criteria you should know and think about, before building a package.

This is a list of the overview information in this chapter.

Where to Find Packaging Tasks

Use these references to find step-by-step instructions for building and verifying packages.

What Are Packages?

Application software is delivered in units called packages. A package is a collection of files and directories required for a software product, and is usually designed and built by the application developer after completing the development of the application code. A software product needs to be built into one or more packages so that it can easily be transferred to a distribution medium, be mass produced, and installed by administrators.

A package is a collection of files and directories in a defined format. This format conforms to the Application Binary Interface (ABI), which is a supplement to the System V Interface Definition.

Package Components

The components of a package fall into two categories: package objects, the application files to be installed, and control files, which control how, where, and if the package is installed.

The control files are also divided into two categories: information files and installation scripts. Some of these control files are required and some are optional.

To package your applications, you must first create the required components, and any optional components, that make up your package. Then you can build the package using the pkgmk command.

To build a package, you must provide the following:

The figure below describes the contents of a package.

Figure 1–1 The Contents of a Package

The preceding context and the following context describe the graphic.

Required Package Components

You must create the following components before you build your package:

Optional Package Components

Package Information Files

There are four optional package information files you can include in your package:

Each package information file should have an entry in the prototype file. See Creating Information Files for more information on creating these files.

Package Installation Scripts

Installation scripts are not required. However, you can provide scripts that perform customized actions during the installation of your package. An installation script has the following characteristics.

The four script types are as follows:

See Creating Installation Scripts for a more information on installation scripts.

Things to Think About Before Building a Package

Before building a package, you need to decide whether your product is going to be made up of one or more packages. (Note that many small packages take longer to install than one big package.) Although it is a good idea to create a single package, it is not always possible. If you decide to build more than one package, you need to determine how to segment the application code. This section provides a list of criteria to use when planning to build packages.

Many of the good packaging criteria present trade-offs among themselves. It will often be difficult to satisfy all requirements equally. These criteria are presented in order of importance; however, this sequence is meant to serve as a flexible guide depending on the circumstances. Although each of these criteria is important, it is up to you to optimize these requirements to produce a good set of packages.

For more design ideas, see Chapter 6, Advanced Package Creation Techniques.

Make Packages Installable Remotely

All packages must be installable remotely. Being installable remotely means that the administrator installing your package might be trying to install it on a client system, not necessarily to the root file system where the pkgadd command is being executed.

Optimize for Client-Server Configurations

Consider the various types of system software configurations (for example, standalone and server) when laying out packages. Good packaging design divides the affected files to optimize installation of each configuration type. For example, the contents of root (/) and usr should be segmented so that server configurations can easily be supported.

Package by Functional Boundaries

Packages should be self-contained and distinctly identified with a set of functionality. For example, a package containing UFS should contain all UFS utilities and be limited to only UFS binaries.

Packages should be organized from a customer's point of view into functional units.

Package Along Royalty Boundaries

Put code that requires royalty payments due to contractual agreements in a dedicated package or group of packages. Do not disperse the code into more packages than necessary.

Package by System Dependencies

Keep system-dependent binaries in dedicated packages. For example, the kernel code should be in a dedicated package with each implementation architecture corresponding to a distinct package instance. This rule also applies to binaries for different architectures. For example, binaries for SPARC-based system would be in one package and binaries for an IA based system would be in another.

Eliminate Overlap in Packages

When constructing packages, eliminate duplicate files whenever possible. Unnecessary duplication of files results in support and version difficulties. If your product has multiple packages, repeatedly compare the contents of these packages for redundancies.

Package Along Localization Boundaries

Localization-specific items should be in their own package. An ideal packaging model would have a product's localizations delivered as one package per locale. Unfortunately, in some cases organizational boundaries may conflict with the functional and product boundaries criteria.

International defaults can also be delivered in a package. This would isolate the files necessary for localization changes and standardize delivery format of localization packages.

Packaging Commands, Files, and Scripts

The purpose of this section is to describe the commands, files, and scripts you might use when manipulating packages. They are described in man pages and in detail throughout this book, in relation to the specific task they perform.

The table below shows the commands available to help you build, verify, install, and obtain information about a package.

Table 1–1 Packaging Commands




For More Information, Go To ... 

Create packages 


Generate a prototype file for input to the pkgmk command

Creating a prototype File With the pkgproto Command


Create an installable package 

Building a Package

Install, remove, and transfer packages 


Install a software package onto a system 

Installing Software Packages


Store answers to a request script 

Design Rules for request Scripts


Copy packages onto a distribution medium 

Transferring a Package to a Distribution Medium


Remove a package from a system 

Removing a Package

Obtain information about packages 


Check consistency of a software package 

Verifying the Integrity of a Package


Display software package information 

The pkginfo Command


Display package parameter values 

The pkgparam Command

Modify installed packages 


Incorporate a new package object into an already installed package 

Design Rules for Procedure Scripts and Chapter 5, Package Creation Case Studies


Remove a package object from an already installed package 

Design Rules for Procedure Scripts

The table below shows the information files available to help you build a package.

Table 1–2 Package Information Files



For More Information, Go To ... 


Package installation defaults file 

The Administrative Defaults File


Package compatibility file 

Defining Package Dependencies


Package copyright information file 

Writing a Copyright Message


Package dependencies file 

Defining Package Dependencies


Package characteristics file 

Creating a pkginfo File


Package contents description file 

The pkgmap File


Package information file 

Creating a prototype File


Package disk space requirements file 

Reserving Additional Space on a Target System

The table below describes optional installation scripts that you can write that affect if and how a package is installed.

Table 1–3 Package Installation Scripts



For More Information, Go To ... 


Solicit information from the installer. 

Writing a request Script


Gather file system data. 

Gathering Data With the checkinstall Script


Perform any custom installation requirements before class installation. 

Writing Procedure Scripts


Perform any custom installation requirements after all volumes are installed. 

Writing Procedure Scripts


Perform any custom removal requirements before class removal. 

Writing Procedure Scripts


Perform any custom removal requirements after all classes have been removed. 

Writing Procedure Scripts

Class Action 

Perform a series of actions on a specific group of objects. 

Writing Class Action Scripts