-This is a smarter version of the -a flag, that is used in some rare
-circumstances. It understands that if the control file lists "Architecture: i386"
-for the package, the package should not be acted on on other architectures. So
-this flag makes the command act on all "Architecture: any" packages, as well
-as on any packages that have the current architecture explicitly specified.
-Contrast to the -a flag, which makes the command work on all packages that
-are not architecture independent.