Central is a passive registration system for Tcl extensions and programs,
based on the idea and workings of the Tcl *pkgconfig* command.
To participate, a *pkgconfig* command should exist in the namespace
of an extension or program ("package").
Central itself is not needed by a providing package, only by a querying program.
Central can be used by a program to scan the namespace hierarchy (*discover*),
and query any package information found.
The *pkgconfig* command provided by a package should
behave like the Tcl *pkgconfig* command.
Central makes no effort to interpret the information returned by a
*pkgconfig* command; this information is entirely up to the package.
Central is all about "about": allowing a program to easily
provide information about itself to the outside world.
The usage example files, the program centraltool.tcl, and
the Central extension itself contain *pkgconfig* commands and other
code bits that can be copied or serve as examples and should make it easy
to add Central functionality to extensions or programs.
Central works with Jim as well as with Tcl.