Re: virtual package? aptitude says "not a real package".

[furufuru@ccsr.u-tokyo.ac.jp]

Kumar Appaiah wrote:

> On my system, apt-cache show emacs-dl-wn gives me black, install says
> that package is unavailable.

Thanks for your response!  I'm still puzzled.  What's this "ghost"
package, then?  The "mplayer" package seems to be another example.
If they are unavailable, then why do they show up when you type

   $ aptitude search mplayer

for example.  What does this mean?

> I think virtual packages are those which are actually generic software
> which have many options fitting the bill. For example, exim4, postfix,
> esmtp-run, sendmail etc. all `provide' the `mail-transport-agent'
> virtual package.
>
> See:
> http://www.debian.org/doc/FAQ/ch-pkg_basics.en.html#s-virtual

Thanks. That matches my understanding of virtual packages.

Regards,
Ryo