Quick Start Guide

yourself (for example, the most recent GNOME packages). They can be identied
by the name extension -devel, such as the packages alsa-devel, gimp-devel, and
libkde4-devel.
9.2.1 Verifying Package Authenticity
RPM packages have a GPG signature. To verify the signature of an RPM package,
use the command rpm --checksig
package
-1.2.3.rpm to determine whether the
package originates from Novell/SUSE or from another trustworthy facility. This is
especially recommended for update packages from the Internet.
9.2.2 Managing Packages: Install, Update, and Uninstall
Normally, the installation of an RPM archive is quite simple: rpm -i
package
.rpm.
With this command the package is installed, but only if its dependencies are fullled
and if there are no conicts with other packages. With an error message, rpm requests
those packages that need to be installed to meet dependency requirements. In the
background, the RPM database ensures that no conicts arise—a specic le can
only belong to one package. By choosing dierent options, you can force rpm to ignore
these defaults, but this is only for experts. Otherwise, you risk compromising the in-
tegrity of the system and possibly jeopardize the ability to update the system.
The options -U or --upgrade and -F or --freshen can be used to update a package
(for example, rpm -F
package
.rpm). This command removes the les of the old version
and immediately installs the new les. The dierence between the two versions is
that -U installs packages that previously did not exist in the system, but -F merely
updates previously installed packages. When updating, rpm updates conguration
les carefully using the following strategy:
If a conguration le was not changed by the system administrator, rpm installs
the new version of the appropriate le. No action by the system administrator
is required.
If a conguration le was changed by the system administrator before the update,
rpm saves the changed le with the extension .rpmorig or .rpmsave (backup le)
and installs the version from the new package (but only if the originally installed
le and the newer version are dierent). If this is the case, compare the backup
le (.rpmorig or .rpmsave) with the newly installed le and make your changes
again in the new le. Afterwards, be sure to delete all .rpmorig and .rpmsave
les to avoid problems with future updates.
.rpmnew les appear if the conguration le already exists and if the noreplace
label was specied in the .spec le.
Following an update, .rpmsave and .rpmnew les should be removed after comparing
them, so they do not obstruct future updates. The .rpmorig extension is assigned if
the le has not previously been recognized by the RPM database.
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