Possible arguments: (none), dirs
Make files or directories 'unique', by adding a prefix or
      suffix.  If the dirs argument is used, the
      port needs a prefix (and only a prefix) based on
      UNIQUE_PREFIX for standard directories
      DOCSDIR, EXAMPLESDIR,
      DATADIR, WWWDIR,
      ETCDIR.  These variables are available for
      ports:
UNIQUE_PREFIX: The prefix to be used
	  for directories and files.  Default:
	  ${PKGNAMEPREFIX}.
UNIQUE_PREFIX_FILES: A list of files
	  that need to be prefixed.  Default: empty.
UNIQUE_SUFFIX: The suffix to be used
	  for files.  Default:
	  ${PKGNAMESUFFIX}.
UNIQUE_SUFFIX_FILES: A list of files
	  that need to be suffixed.  Default: empty.
All FreeBSD documents are available for download at https://download.freebsd.org/ftp/doc/
Questions that are not answered by the
    documentation may be
    sent to <freebsd-questions@FreeBSD.org>.
    Send questions about this document to <freebsd-doc@FreeBSD.org>.