mirror_sites.tcl and `:nosubdir` tag

[petr]

Hi all,

in ticket #47571 (https://trac.macports.org/ticket/47571) I am proposing a small addition to mirror_sites.tcl. However, I do not fully understand the function and use of the tag `:nosubdir`. There is some comment in the file

{{{
# Appending :nosubdir as a tag to a mirror, means that
# the portfetch target will NOT append a subdirectory to
# the mirror site.
}}}

but I still do not understand which effect it will have if this tag was appended. Can anybody comment on this!

Thanks!
~petr