Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!mcvax!hp4nl!dutrun!winfave
From: winfave@dutrun.UUCP (Alexander Verbraeck)
Newsgroups: comp.lang.pascal
Subject: Re: Pointers / Linked lists with files..
Summary: 550+ kbytes structure is too large
Message-ID: <722@dutrun.UUCP>
Date: 14 May 89 12:46:53 GMT
References: <5708@cs.Buffalo.EDU> <1389@bucket.UUCP> <3377@westfort.UUCP>
Organization: Delft University of Technology, The Netherlands
Lines: 31

I suppose you are using Turbo Pascal on a personal computer
(because of your use of the string[..] construction).
The problem the compiler has with this record construction is
that it is awfully large. A quick calculation showed, that the
array structure uses more than 550 kbytes of memory. That is more
than is available for a structure. The largest possible single
structure in Turbo Pascal is 64 kbytes. This means, that one
record fits easily in memory ("only" 11 kbytes) but the whole
structure does not.

I would suggest writing the records to the file one by one. If you
need another record, write the one you had currently in memory and
read the one you need. If you want to skip to the next "array of
records", use a Seek command to position the filepointer into the
right position. This means, that you have to use a command like:

     Seek(file,StructureNumber*50+IndexNumber);

The StructureNumber denotes the number of the "total" structure you
want to access (the one of 550+ kbytes). The IndexNumber is the
index IN the original array[1..50].

I hope this helps... If you have any questions or remarks, please post
a reply or mail me directly.

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Alexander Verbraeck                            e-mail:
Delft University of Technology                 winfave@hdetud1.bitnet
Department of Information Systems              winfave@dutrun.uucp
PO Box 356, 2600 AJ  The Netherlands
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