Download O`reilly Building Embedded Linux Systems

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One thing that distinguishes commercial distributions from open source distributions is the
support provided by the vendor. Whereas the vendor supplying a commercial distribution
almost always provides support for her own distribution, the open source community supplying
an open source distribution does not necessarily provide the same level of support that would
be expected from a commercial vendor. This, however, does not preclude some vendors from
providing commercial support for open source distributions. Through serving different
customers with different needs in the embedded field, the various vendors build a unique
knowledge about the distributions they support and the problems clients might encounter
during their use, and are therefore best placed to help you efficiently. Mainly, though, these
vendors are the ones who keep up with the latest and greatest in Linux and are therefore the
best source of information regarding possible bugs and interoperability problems that may
show up.
Reputation can also come into play when choosing a distribution, but it has to be used wisely,
as a lot of information circulating may be presented as fact while being mere interpretation. If
you've heard something about one distribution or another, take the time to verify the validity of
the information. In the case of a commercial distribution, contact the vendor. Chances are he
knows where this information comes from and, most importantly, the rational explanation for it.
This verification process, though, isn't specific to embedded Linux distributions. What is
specific to embedded Linux distributions is the reputation commercial distributions build when
their vendors contribute to the open source community. A vendor that contributes back by
providing more open source software or by financing development shows that he is in contact
with the open source community and has therefore a privileged position in understanding how
the changes and developments of the various open source projects will affect his future
products and ultimately his clients. In short, this is a critical link and a testament to the vendor's
understanding of the dynamics involved in the development of the software he provides you. In
the case of open source distributions, this criterion is already met, as the distribution itself is an
open source contribution.
Another precious tool commercial distributions might have to offer is documentation. In this day
and age where everything is ever-changing, up-to-date and accurate documentation is a rare
commodity. The documentation for the majority of open source projects is often out of date, if
available at all. Linus Torvalds' words ring true here. "Use the source, Luke," he says, meaning
that if you need to understand the software you should read the source code. Yet not everyone
can invest the amount of time necessary to achieve this level of mastery, hence the need for
appropriate documentation. Because the open source developers prefer to invest time in
writing more code than in writing documentation, it is up to the distribution vendors to provide
appropriately packaged documentation with their distributions. When evaluating a distribution,
make sure to know the type and extent of accompanying documentation. Although there is less
documentation for open source distributions, in comparison with commercial distributions,
some open source distributions are remarkably well documented.
Given the complexity of some aspects of development and target setup, the installation of a
development and/or target distribution can be hard. In this regard, you may be looking for easy-