What is the #prelink# stuff for?

[James Wilkinson]

Daniel B. Thurman wrote:
> I was cleaning my mess in my filesystems and I came across
> a few #prelink# file and need to ask what to with these files.
> 
> I have:
> 
> /usr/lib/libgnomeui-2.so.0.1000.0.#prelink#.Hoth6j
> /usr/lib/libgnomeui-2.so.0.1000.0.#prelink#.6kdQ3D
> /usr/sbin/edquota.#prelink#.BxAQFF
> /usr/bin/ktalkd.#prelink#.DMTn4f
> /usr/bin/krfb.#prelink#.p2u2gp
> /usr/bin/knewstickerstub.#prelink#.X0ybM8
> /sbin/quotacheck.#prelink#.YZqcuk
> 
> I have to keep the following:
> 
> lrwxrwxrwx /usr/lib/libgnomeui-2.so.0 -> /usr/lib/libgnomeui-2.so.0.1000.0.#prelink#.Hoth6j

Normally a result of the prelink program. This "pre-links" other
programs, doing stuff that would otherwise have to be done at run-time.
This speeds things up in normal operation.

However, it doesn't always work properly...

If those files are zero size, then you can delete them safely.

You may want to run /etc/cron.daily/prelink again to see if it tidies
stuff up.
> Also, when I did a 'yum update', invariably I get some *.rpmnew
> files so what do I need to do with these as well?  Can I toss
> them out without any consequences?

Many RPMs come with configuration files, or other files that might be
edited. This can be a problem when you update an RPM: the new RPM may
come with modified configuration files.

If you've carefully edited a configuration file for your site, you don't
really want it over-written with the new default configuration file. But
by the same token, you might actually want some of the features from the
new configuration file, especially if they turn on new functionality.

So RPM saves the new files with an .rpmnew extension. It's up to you to
take a look at your existing files and the new files and come up with a
new, combined configuration file.

Occasionally, RPM will install the new configuration file anyway. This
is usually because the configuration file format has changed, and the
old one will no longer work. If this happens, the old file will be saved
with a .rpmsave extension.

This rarely happens: few programmers like putting their users through
the pain of incompatible configuration file formats. [1]

Hope this helps,

James.

[1] For example, take a look at sendmail.cf, the archetypal
nearly-incomprehensible configuration file. These days the
recommendation is that you should never edit it directly, but use a
set of different configuration files to generate it. But they still
won't play around with the sendmail.cf format, because of all the
currently-working hand-crafted sendmail.cf's around to handle various
sites's special needs.

-- 
E-mail address: james | SSH over the mobile on orange GPRS though, has the
@westexe.demon.co.uk  | latency of the sat, and the bandwidth of wet string. I
                      | might be insulting wet string though.
                      |     -- Chloe