Using the Red Hat Package Manager

The Red Hat Package Manager’s primary function is to allow the installation and removal of files (typically precompiled software). It is easy to use, and several graphical interfaces have been built around it to make it even easier. Red Hat, Mandrake, and other distributions use this tool to distribute their software. In fact, almost all of the software mentioned in this book is available in RPM form. The reason for going through the process of compiling software yourself in other modules is that you can use compile-time options that are not available in an RPM. Basically, an RPM file is a collection of all the files necessary for a particular program to
run. It also includes descriptions of the program, version information, and the necessary scripts to perform the installation itself.

NOTE
In this context, I am assuming that the RPM files contain precompiled binaries. Several groups, such as Red Hat, also make source code available as an RPM, but it is uncommon to download and compile source code in this fashion.

The RPM tool performs general management of all of the RPM packages that are installed on a given host. This includes tracking which packages are installed, their version numbers, and their file locations. All of this information is kept in a simple database file on the host.

In general, software that comes in the form of an RPM is less work to install and maintain than software that needs to be compiled. The trade-off is that by using an RPM, you accept the default parameters supplied in the RPM. In most cases, these defaults are acceptable. However, if you need to be more intimately aware of what is going on with a service, you may find that compiling the source yourself will prove more educational about what package components exist and how they work together. But assuming that all you want to do is install a simple package, RPM is perfect. There are several great resources for RPM packages, including the following:

● http://www.rpmfind.net
● http://www.freshrpms.net
● http://www.linuxapps.com
● ftp://ftp.redhat.com/pub/contrib

Of course, if you are interested in more details about RPM itself, you can visit the RPM web site at http://www.rpm.org. RPM comes with Red Hat Linux (and derivatives) as well as Caldera Linux. If you aren’t sure if RPM comes with a particular distribution, check with your vendor.

NOTE
Although the name of the package manager says “Red Hat,” the software can be used
with other distributions as well. In fact, RPM has even been ported to other operating
systems, such as Solaris and IRIX! The source code to RPM is open-source software, so
anyone can take the initiative to make the system work for them.