Re: dpkg seems not to 'see' virtual package installed.

[Jonathan Nieder <jrnieder@gmail.com>]

Hi Alex,

Prekates Alexandros wrote:

> cnijfilter-common depends from libcupsys2 (>= 1.2.1). But:
> Package libcupsys2 in not installed

The meaning of dependencies is spelled out in full in the Debian
policy manual (which is the closest we have to a high-level manual for
dpkg).  It says[1]:

	If a relationship field has a version number attached, only
	real packages will be considered to see whether the
	relationship is satisfied 

The code agrees[2].

      /* If there was no version specified we try looking for Providers. */
      if (possi->verrel == dvr_none) {

I believe it would be possible to diagnose this better, though ---
for example: in addition to

	 cnijfilter-common depends on libcupsys2 (>= 1.2.1)
	  libcupsys2 is not installed but configs remain

to say something like

	  libcup2 provides libcupsys2, but virtual packages have no version

If you would like to work on that, I'd be glad ot provide any help
I can.

Regards,
Jonathan

[1] http://www.debian.org/doc/debian-policy/ch-relationships.html#s-virtual
[2] src/depcon.c::depisok