Specifications

Red Hat Enterprise Linux to Oracle Solaris Porting Guide
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• Signature:
The signature contains size, checksums, and other such package signatures.
• Tagged data:
Tags are grouped together at the top of the file in a section known as the preamble. The tagged data
gives information about the contents of the package; this section contains mandatory and optional
information (tags), for example, the NAME tag (mandatory) holds the package name, the PRE tag
(optional) holds a pre-installation script (the script that the rpm command runs prior to installing
the files).
The tags within a package follow a specific format: tag:data. The tag is separated from its
associated data by a colon.
Typical tag types found in an RPM package include the following:
− Package naming tags
− Architecture-specific tags
− Operating system tags
− Dependency tags
− Directory-related tags
− Source and patch tags
− Descriptive tags
Under each of these categories, there can be several flags. For example, under the Dependency tag
category, there are tags such as the requires tag, the conflicts tag, the provides tag, and
son on.
• Payload:
The payload section specifies the files to be installed on the target system.
Categories of RPM Packages
RPM packages can mainly be divided into two categories:
• Binary packages (RPMs):
A binary RPM is compiled for a particular architecture, for example, the GCC compiler and tools
compiled for an Intel i686 target. You would need separate packages for each targeted platform; the
same package won’t work on other hardware platforms.
• Source Code Packages (RPMs):
These RPMs packages provide the source code for other packages.