question: maintaining patch separately from ports cvs

[Mohacsi Janos]

Dear All,
	Are there any possible way to maintain a local patch against a
certain port.
	Let's consider a following scenario:
- There is port named foo/bar that is maintained and constantly updated by
the certain maintainer of FreeBSD foo/bar port.
- Somebody wants to use the port, but a heavily modified way e.g.:
patched setup in chroot, jail environment, setup with certain
configuration defaults, that is extremely local specific

How can one achieve such scenario without interfering the FreeBSD port
system and benefiting the regular update of the port?

Best Regards,

Janos Mohacsi
Network Engineer, Research Associate
NIIF/HUNGARNET, HUNGARY
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