Page 79 - DCAP106_OPERATING_SYSTEM_TOOLS

Operating System Tools

Notes Pristine Sources: A crucial design goal was to allow the use of “pristine” software sources, as
distributed by the original authors of the software. With RPM, you have the pristine sources
along with any patches that were used, plus complete build instructions. This is an important
advantage for several reasons. For instance, if a new version of a program comes out, you do not
necessarily have to start from scratch to get it to compile. You can look at the patch to see what
you might need to do. All the compiled-in defaults, and all of the changes that were made to get
the software to build properly are easily visible using this technique.

Did u know? The goal of keeping sources pristine may only seem important for developers,
but it results in higher quality software for end users, too.

Self Assessment

Fill in the blanks:
4. Any configuration files that you modified are preserved during .....................................

5. A crucial design goal was to allow the use of “.....................................” software sources, as
distributed by the original authors of the software.

4.3 The RPM Command Line Tool

The RPM Package Manager (RPM) is a powerful command line driven package management
system capable of installing, uninstalling, verifying, querying, and updating computer software
packages.

4.3.1 Installing a New Package

The install mode, as its name suggests, is used to install RPM packages onto your system.
Installing a package is accomplished with the -i option:
# rpm -i penguin-3.26.i386.rpm
Before installing the package, RPM performs several checks. First, it makes sure the package
you are trying to install isn’t already installed. RPM won’t let you install a package on top of
itself. It also checks that you are not installing an older version of the package. Next, RPM does a
dependency check. Some packages depend on other packages being installed first.

Example: In the example given below, you have just downloaded the latest RPM version
of Penguin utilities and now want to install it.
# rpm -i penguin-3.26.i386.rpm
failed dependencies:
iceberg >= 7.1 is needed by penguin-3.26.i386.rpm

This error indicates the penguin package failed to install because it requires the iceberg package
with a version equal to or greater than 7.1. You’ll have to find and install the iceberg package, and
any packages iceberg requires.

Finally, RPM checks to see if any configuration files would be overwritten by the installation of
this package. RPM tries to make intelligent decisions about what to do with conflicts. If RPM
replaces an existing configuration file with one from the new package, a warning will be printed
to the screen.

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