Package pkg-order-1.12-5

It does dependency checks, if you wish. It knows the difference between installed, new (and available) packages, and the relationship fields (pre-depends, depends, recommends, and suggests). (For example, the current packages list need not be read in unless you want dependency checks; you may already have done that and now merely wish an ordering). It comes with a Test::Harness test suite, to protect the world against my typos. Oh, it knows about epochs as well if your dpkg does. This could be the basis of mass compiling the packages on a new architecture, or to build a release from scratch. It creates associative arrays of currently installed packages (/var/lib/dpkg/status), and new packages (given a packages file at the command line). Then, in the checking dependency phase, for each package in the new packages list, it looks at the dependencies, and ensure that each dependency is satisfied in either the new list or the installed list. If the directive is satisfied from the list of new packages, that package is added to the list of packages to be topographically sorted. It understands Pre-Depends and will insert breaks into the sorted list to separate the installation process into separate runs as required to satisfy Pre-Dependencies. All this is a set of perl5 libraries, so people may use the API in their own scripts.