src/pl/tcl/modules/README

Regular Tcl scripts of any size (over 8K :-) can be loaded into
the table pltcl_modules using the pltcl_loadmod script. The script
checks the modules that the procedure names don't overwrite
existing ones before doing anything. They also check for global
variables created at load time.

All procedures defined in the module files are automatically
added to the table pltcl_modfuncs. This table is used by the
unknown procedure to determine if an unknown command can be
loaded by sourcing a module. In that case the unknown procedure
will silently source in the module and reexecute the original
command that invoked unknown.

I know, this readme should be more explanatory - but time.

Jan