Running Linux, 5th Edition - Matthias Kalle Dalheimer [221]
The next task is to initialize the RPM database. Distributions that come with RPM do the initialization automatically, but on other systems you will have to issue the following command:
tigger # rpm --initdb
This command creates several files in the directory /var/lib/rpm. The directory /var/lib should already exist; if it doesn't, create it with the mkdir command first.
Now you can install RPM packages the normal way, but because you have not installed the basic parts of the system, such as the C library with RPM, you will get errors like the following:
tigger # rpm -i SuperFrob-4.i386.rpm
failed dependencies:
libm.so.5 is needed by SuperFrob-4
libdl.so.1 is needed by SuperFrob-4
libc.so.5 is needed by SuperFrob-4
because those files are not recorded in the RPM database. Of course, you really do have those files on your system; otherwise most programs wouldn't run. For RPM to work, you must tell it not to care about any dependencies. You do this by specifying the command-line option --nodeps:
tigger # rpm -i --nodeps SuperFrob-4.i386.rpm
Now, RPM will install the package without complaining. Of course, it will run only if the libraries it needs are installed. The mere fact that you use --nodeps doesn't save you when the "dependent" library or software is not installed on your system.
With this information, you should be able to administer your RPM-based system. If you want to know more, read the manual page for the rpm command, or check out http://www.rpm.org.
Some commercial companies sell automated upgrade services based on RPM. As a subscriber to these services, you can have your system upgraded automatically; the service finds out which new packages are available and installs them for you. If you use the SUSE distribution, SUSE provides such a service (called "YOU") for free. Even the Debian distribution (whose package system is described in the next section) has an automated upgrade system (described there). However, some security experts consider these automated upgrades a security risk.
Using dpkg and apt
After rpm, the most popular package manager for Linux distributions is dpkg, which is used to manage .deb archives. As the name implies, the .deb format is tied to the Debian distribution, so it is also used by distributions based on Debian, such as Ubuntu and Kubuntu, Libranet, and Xandros. Like the RPM format, the .deb format keeps track of dependencies and files to help ensure your system is consistent.
The technical differences between the two formats are actually fairly small; although the RPM and .deb formats are incompatible (for example, you can't install a Debian package directly on Red Hat), you can use alien to translate .deb packages for other distributions (and vice versa). The main difference between the formats is that .deb packages are built using tools that help make sure they have a consistent layout and generally conform to policies (most notably, the Debian Policy Manual, provided in the debian-policy package) that help developers create high-quality packages.
While dpkg is the low-level interface to the Debian package manager, most functions are usually handled through either the apt suite of programs or frontends such as dselect, aptitude, gnome-apt, synaptic, or KPackage.
Installing .deb packages on a Debian system is quite easy. For example, if you have a package named superfrob_4-1_i386.deb, you can install it with:
tigger # dpkg -i superfrob_4-1_i386.deb
Selecting previously deselected package superfrob.
(Reading database ... 159540 files and directories currently installed.)
Unpacking superfrob (from superfrob_4-1_i386.deb) ...
Setting up superfrob (4-1) ...
If the superfrob package is missing a dependency, dpkg will issue a warning message:
tigger # dpkg -i