[manual] for in structures

[Francesco Potorti`]

>Are you using Mercurial?  If so, could you please submit future
>patches by committing to your local archive and then exporting the
>change with "hg export", and then sending the resulting changeset as a
>plain/text attachment?

I just installed mercurial, but I do not know anything about it.
I'll try next time.

I have used sccs, rcs, cvs, and normally I use Emacs' cv interface to
all of them, but I fear that vc does not support the 'export' command.