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Date: Tue, 7 Apr 2009 10:35:07 -0500 (CDT)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Christian Henning <chhenning@gmail.com>
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Cc: libtiff - Liste <tiff@lists.maptools.org>
Subject: Re: [Tiff] Writing tiff to in-memory buffer
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On Tue, 7 Apr 2009, Christian Henning wrote:

> Ok, my read function was wrong. Since I only want to write into the
> buffer the read procedure should return 0 and not the size read.
> Fixing that gives me a valid TIFF*. I also need to setup my seek_proc
> to prohibit it from seeking on an empty ostream. Doing though would
> raise the failbit. I don't understand why TIFFClientOpen is calling
> seek_proc( 0,0). It seems redundant to me.

Without thoroughly analyzing the code, (and making a WAG) I get the 
impression that libtiff reads back the header it just wrote to obtain 
the actual endianness of the data and the TIFF subformat.

It is also true that a write stream should be flushed before depending 
on data being in the file.

Bob
--
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/
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