Dumping data structures with circular references.

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Date: Fri, 3 Nov 89 09:19 PST
From: Robert D. Pfeiffer <RDP@ALAN.LAAC-AI.Dialnet.Symbolics.COM>
Subject: Dumping data structures with circular references.
To: SLUG@ALAN.LAAC-AI.Dialnet.Symbolics.COM
In-Reply-To: <19891102190650.0.RDP@THOMAS.LAAC-AI.Dialnet.Symbolics.COM>
Message-ID: <19891103171925.1.RDP@THOMAS.LAAC-AI.Dialnet.Symbolics.COM>

    Date: Thu, 2 Nov 89 11:06 PST
    From: Robert D. Pfeiffer <RDP@ALAN.LAAC-AI.Dialnet.Symbolics.COM>

    I'd like to know what people do in general to avoid the "circular
    reference" problem when using SYS:DUMP-FORMS-TO-FILE.  I would guess
    that this must have been solved many times but the documentation doesn't
    seem to have anything to say about it.  

    [...]

Many thanks for the replies so far (keep those cards and letters
coming!).  I'm pursuing one additional item on this topic and it
involves dumping the data in two passes.  The problem is that
SYS:DUMP-FORMS-TO-FILE takes a filename rather than a stream and it
doesn't allow me to say "append".  

Anyone have an idea how best to solve this?  Maybe write two separate
files with SYS:DUMP-FORMS-TO-FILE and then append them after the fact?
Is it easy to append two binary files (or are there subtleties of the
file format that will screw me)?  Or if I had the equivalent of
SYS:DUMP-FORMS-TO-STREAM I guess I would be home free.  Then, I could
simply do my own WITH-OPEN-FILE once and call SYS:DUMP-FORMS-TO-STREAM
twice on it.

Thanks again for any insight on this topic.