Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!crdgw1!sagittarius!dixon
From: dixon@sagittarius.crd.ge.com (walt dixon)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Retrieving the value of FILES=???
Keywords: Global File Handle Table
Message-ID: <8571@crdgw1.crd.ge.com>
Date: 14 Jun 90 21:00:09 GMT
References: <605@digigw.digital.co.jp> <4057@jato.Jpl.Nasa.Gov>
Sender: news@crdgw1.crd.ge.com
Reply-To: dixon@sagittarius.crd.ge.com (walt dixon)
Organization: General Electric Corp. R&D, Schenectady, NY
Lines: 37

In article <4057@jato.Jpl.Nasa.Gov> Kaleb Keithley writes:

>In article <605@digigw.digital.co.jp> gday@digigw.digital.co.jp
> (Gordon Day) wr:
>>I am confronted with the problem of finding out length of the global file
>>handle table in DOS (>=3.3).  I am aware of the following issues:
>>
>> [ much deleted ]

>How about: (in psuedo-code)

>#ifdef DOS
>    fopen ("/CONFIG.SYS", "r");
>    fscanf (..., "FILES=", ...);
>    fscanf (...,  value, ...);
>    fclose (...);
>#else
>    other method appropriate for architecture
>#end

>Since all DOS machines have to have CONFIG.SYS in the root directory, it
>would work for any DOS box.  If the fopen fails, then assume the default.

This technique should work in almost all cases.  The parsing logic should
be a little smarter because it is possible to "comment" out lines in
CONFIG.SYS.  Its also possible to grow the System File table after boot
by linking a memory block to the existing chain.  Finally as Kaleb notes
there is the posibility that the open will fail.  I still prefer traversing
the SFT blocks.

Walt Dixon	{internet:	dixon@crd.ge.com	}
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Walt Dixon dixon@crd.ge.com