Unclear wording on Pre-Depends relation (page 210)More...
Reported on: 2006-01-30
In chapter 5. The Debian package management system on page 210:
The description of the Pre-Depends relation as part of the discussion of the Depends relation in section 5.7.3 is unclear. A better explanation is:
Another relation, Pre-Depends, provides a tighter dependency and is only used in very special cases;
packages listed here need to be fully configured before the dependending package can be unpacked or configured. If a previous version of the pre-dependent package has once been configured on the system, the depending package can be unpacked (but not configured) even if the current version of the pre-dependent package has not been configured yet.
In a certain sense, Pre-Depends is more relaxed than Depends and is thus used to work around some situations in which a plain Depends would not be suitable. However, from a technical perspective, the dependency is tighter.
The relevant section of the Debian Policy has since been updated to draw a clearer picture.