That would normally be handled with patch files.
See the update-patches parts of
https://www.openbsd.org/faq/ports/guide.html

and the bsd.port.mk(5) manual page.

You'll also want to increment REVISION in the port's Makefile.

On Tue, Aug 26, 2025 at 03:17:15AM -0400, Peter Moss wrote:
> Thank you Jonathan,
> 
> I works. I was able to download the source code and compile it.
> 
> Just a newbie question.
> 
> I see the sources have been downloaded to distfiles and compiled from there.
> 
> If I want to update (locally) the sources in this package, I have to update
> the
> tar.gz file? I only see the sources untared in the pbj directory and are
> recreated
> every time I do make clean;make build. Is that how this package building
> works?
> 
> Thank you,
> Peter
> 
> On 8/26/25 02:14, Jonathan Gray wrote:
> > On Tue, Aug 26, 2025 at 02:02:02AM -0400, Peter Moss wrote:
> > > The makefile for sysutils/xbatt
> > > 
> > > https://cvsweb.openbsd.org/cgi-bin/cvsweb/ports/sysutils/xbatt/Makefile?rev=1.32&content-type=text/x-cvsweb-markup
> > > 
> > > points to
> > > 
> > >     http://www.clave.gr.jp/~eto/xbatt/
> > > 
> > > however this site is not reachable.
> > > 
> > > As a result I am unable to review and compile the source code.
> > It will download from elsewhere after a timeout.
> > 
> > $ make fetch
> > ===>  Checking files for xbatt-1.2.1p5
> > > > Fetch http://www.clave.gr.jp/~eto/xbatt/xbatt-1.2.1.tar.gz
> > ftp: connect: Operation timed out
> > > > Fetch https://ftp.openbsd.org/pub/OpenBSD/distfiles/xbatt-1.2.1.tar.gz
> > xbatt-1.2.1.tar.gz 100% |*******************************| 12779       00:00
> 
>