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swinstall and swremove. Using chroot prevents modification of files on the booted
system image. Such use of chroot is sometimes known as a chroot jail.
• SW_SESSION_IS_DRD – drd runcmd sets the environment variable
SW_SESSION_IS_DRD to 1 when it is executed. Packaging control scripts can use this
variable to check for the presence of a runcmd environment.
• Packaging – Restrictions on software packages are needed to ensure that the booted system
image is not modified. A software package that conforms to these restrictions is known as
DRD-safe
.
The remainder of this document describes what it means to be DRD-safe and how to create DRD-safe
packages.
1.2 Purpose of Document
After reading this document, the reader should be able to accomplish both of the following:
• Identify unsafe logic in a software package or application and implement appropriate
revisions to make the package or application DRD-safe
• Create DRD-safe packaging
1.3 Audience
This document is intended to be used by software packagers and software developers as a source of
information about DRD-safe issues and guidelines.
1.4 Release Information
The DRD utilities are supported on both HP-UX 11i v2 and 11i v3. For 11i v2, HP-created patches
are required to be DRD-safe. Non-patch products and filesets for 11i v2 can be DRD-safe, but they
are not required to be DRD-safe. All HP-created 11i v3 and later packages (patches and products)
are required to be DRD-safe.
1.5 Terms and Definitions
Term Definition
booted system
environment
The system environment that is currently running, also known as the current, active,
or running system environment
.
CLI
Command line user interface
clone
• (noun) clone – a system image clone
• (verb) clone – to clone a system image
cloned system image
A copy of the critical file systems from the system image of a booted system image,
produced by the drd clone command.
A cloned system image may be inactive, or the cloned system image may be booted,
in which case the system activities are started and the clone becomes the system
image in the booted system image. When a particular system image is booted, all
other system images are inactive.
A system administrator may modify a cloned system image by installing software on
it using the drd runcmd command
.
control scripts
Shell scripts provided with software packages that are used to customize the install
or other software management operation
.