Chapter 1. Introduction to RPM
The RPM Package Manager (RPM) is a package management system that runs on Red Hat Enterprise Linux (RHEL), CentOS, and Fedora. You can use RPM to distribute, manage, and update software that you create for any of these operating systems.
The RPM package management system has the following advantages over distributing software in conventional archive files:
- RPM manages software in the form of packages that you can install, update, or remove independently of each other, which makes the maintenance of an operating system easier.
- RPM simplifies the distribution of software because RPM packages are standalone binary files, similar to compressed archives. These packages are built for a specific operating system and hardware architecture. RPMs contain files such as compiled executables and libraries that are placed into the appropriate paths on the filesystem when the package is installed.
With RPM, you can perform the following tasks:
- Install, upgrade, and remove packaged software.
- Query detailed information about packaged software.
- Verify the integrity of packaged software.
- Build your own packages from software sources and complete build instructions.
- Digitally sign your packages by using the GNU Privacy Guard (GPG) utility.
- Publish your packages in a YUM repository.
In Red Hat Enterprise Linux, RPM is fully integrated into the higher-level package management software, such as YUM or PackageKit. Although RPM provides its own command-line interface, most users need to interact with RPM only through this software. However, when building RPM packages, you must use the RPM utilities such as
1.1. RPM packages
An RPM package consists of an archive of files and metadata used to install and erase these files. Specifically, the RPM package contains the following parts:
The GPG signature is used to verify the integrity of the package.
Header (package metadata)
The RPM package manager uses this metadata to determine package dependencies, where to install files, and other information.
The payload is a
cpioarchive that contains files to install to the system.
There are two types of RPM packages. Both types share the file format and tooling, but have different contents and serve different purposes:
Source RPM (SRPM)
An SRPM contains source code and a SPEC file, which describes how to build the source code into a binary RPM. Optionally, the SRPM can contain patches to source code.
A binary RPM contains the binaries built from the sources and patches.
1.2. Listing RPM packaging utilities
In addition to the
rpmbuild(8) program for building packages, RPM provides other utilities to make the process of creating packages easier. You can find these programs in the
rpmdevtoolspackage has been installed:
# yum install rpmdevtools
Use one of the following methods to list RPM packaging utilities:
To list certain utilities provided by the
rpmdevtoolspackage and their short descriptions, enter:
$ rpm -qi rpmdevtools
To list all utilities, enter:
$ rpm -ql rpmdevtools | grep ^/usr/bin
- RPM utilities man pages