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Date: Tue, 27 Jul 2004 09:27:19 -0400
From: Frank Warmerdam <warmerdam@pobox.com>
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To: zhaoguang <zhguang@163.com>
Subject: Re: [Tiff] on modify tags
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zhaoguang wrote:
>  i want to modify some tags of a tiff file, but if i open a file by TIFFOpen with a mode parameter "w", all the context was cleaned, any suggestion on this subject?
> thanks

Zhaoguang,

You can open the file in "update mode" using the access string "r+".
However, libtiff isn't generally oriented to in-place-update so there
are alot of things that can go wrong.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam@pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent

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