update-patches example from guide doesn't work

Hello.

I try to make my first port and going through Porting Guide[1].
It has a example about making patches:

> cd `make show=WRKSRC` ; cp foo/bar.c{,.orig.port}
> edit foo/bar.c to fix the error.
> cd - ; make update-patches
> this will create patches/patch-foo_bar_c with your modifications.

But make ignores files with .orig.port postfix, patches appears
only for just .orig. In man bsd.port.mk we also have only .orig postfix.
apropos .orig.port shows nothing.

I miss something, or it is just a mispell in documentation?


[1]: https://www.openbsd.org/faq/ports/guide.html