Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!hsdndev!cmcl2!adm!news
From: CDCKAB%EMUVM1.BITNET@cunyvm.cuny.edu ( Karl Brendel)
Newsgroups: comp.lang.pascal
Subject: Re: Reading out my FAT part II, please help me!!!
Message-ID: <26990@adm.brl.mil>
Date: 23 May 91 13:29:57 GMT
Sender: news@adm.brl.mil
Lines: 52

Responding to article campbell.674915054@cutmcvax from
  campbell@cutmcvax.cs.curtin.edu.au (Trevor George Campbell CC361):

>CDCKAB%EMUVM1.BITNET@cunyvm.cuny.edu ( Karl Brendel) writes:

>>In article <9857@star.cs.vu.nl> erwvegm@cs.vu.nl (Erwin van Egmond)
>>  wrote:

[... deleted ... now Trevor writes: ]

>You do need to read the FAT as that is the only place that you can
>get the number of the next cluster. DOS uses the FAT to store the
>chain of the Files blocks. The clustor that a file occupies includes
>ONLY the data from the file, and NO pointers to the next cluster
>that a file uses. The cluster number is uses as an offset into the
>FAT to determine the next cluster number. Once you have the cluster
>number of the first cluster then you don't need any more information
>that the FAT for the disk.

Yes, Trevor, that is why I wrote:

>>Only if you then want to trace the file's chain of clusters do you
>>need to access the FAT itself.

The original poster, however, wrote:

>>>  What I want is this :
>>>                        I have a file (Any file) and I want to know
>>>                        at which sector/cluster this file is placed.
>>>                        I want to find this out with TP5.5
>>>                        This means that I'm looking for a program
>>>                        that finds the beginning of my FAT, searches
>>>                        this FAT and returns the sector/cluster number
>>>                        of the file.

He says nothing about actually tracing the chain of allocated
clusters, only about finding the starting cluster. So I wrote:

>>The directory entry for the file includes the starting cluster (two
>>bytes (a word) at offset $1A into the entry).

If he wants to trace the chain, he should say so. Don't you agree?
;)

Cheers--                        --Karl

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| Karl Brendel                           Centers for Disease Control |
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