sub
sub
fetches package,
using fetch
(3),
and adds it to the SUBDIRS variable used by the rules file.
package should be the name of a package
containing a makefile that includes the rules file.
Adding a package to the SUBDIRS variable means that it will be built
and installed as a part (subsystem) of the product. It is important
that make_rules
(3)
also is used, since it includes the rules file that contains the
makefile magic that recurses all SUBDIRS.