> mkisofs: The option '-P' is reserved by POSIX.1-2001.
  > mkisofs: The option '-P' means 'do not follow symbolic links'.
  > mkisofs: Mkisofs-2.01 will introduce POSIX semantics for '-P'.
  > mkisofs: Use -publisher in future to get old mkisofs behavior.

  I can't find a reference to mkisofs in SUSv3, what do I miss?

Even if we accept your failure to find a reference as authoritative
:-), the question remains as to how to handle changing the invocation
of mkisofs so it continues to do what we want.

  Make makefs do iso9660, and forget it.

  Patch it in pkgsrc (seems like a bad idea).

  Change to the new argument, not addressing the validity of the
  POSIX.1 argument.

I would think that we expect people to have pkgsrc bits that are no
older than the current stable branch, although I haven't seen that
explicitly stated.

-- 
        Greg Troxel <gdt@ir.bbn.com>