Page 137 - DCAP602_NETWORK_OPERATING_SYSTEMS_I

Unit 7: Installing Software

important advantage for several reasons. For instance, if a new version of a program comes notes
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.
The goal of keeping sources pristine may only seem important for developers, but it results
in higher quality software for end users, too. We would like to thank the folks from the
BOGUS distribution for originating the pristine source concept.

Task “RPM allows intelligent, fully-automated, in-place upgrades of your system.”
Comment.

7.2 adding and removing packages

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. In this
example, 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.

# rpm -I penguin-3.26.i386.rpm
warning: /etc/someconfig saved as /etc/someconfig.rpmsave

Note It’s up to you to look at both files and determine what modifications, if any,
need to be made.

uninstalling a package

The RPM -e command removes a package from your system. Like Install mode, RPM does some
housekeeping before it will let you remove a package. First, it does a dependency check to make
sure no other packages depend on the package you are removing. If you have modified any of the

LoveLy professionaL university 131