2011.05.05 16:44 "[Tiff] Is LibTiff 3.9.5 Thread Safe ?", by Katerina Sedivy

2011.05.05 19:59 "Re: [Tiff] Is LibTiff 3.9.5 Thread Safe ?", by Katerina Sedivy

Sorry I did not do a reply to all...


Thank you for your response. So you say that you use the TIFFGetField() in a multithread environement on multiple tiffs and it always returns the correct values for the bits per sample flag? You do not do anything special like Bob said about the exercising?



On Thu, May 5, 2011 at 3:03 PM, Frank Warmerdam <warmerdam@pobox.com> wrote:

> On 11-05-05 02:38 PM, Katerina Sedivy wrote:

>> Let me try to explain myself better.. I have 3 folders with multiple tiff >> files. Each thread reads tiff files from a different folder therefore the

>> same
>> tiff file is never opened by 2 threads at the same time.
>> Thread1 reads tiff files from folder Tiffs1
>> Thread2 reads tiff files from folder Tiffs2
>> Thread3 reads tiff files from folder Tiffs3
>> So I would have assumed that TIFFGetField is alway executed on a different

>> object since I open a different tiff file handle each time before calling >> TIFFGetField. The handle to the tiff returned by TiffOpen is a local var

>> in

>> the execute function of the thread therefore it is not one file handle per >> thread but rather one file handle per TIFF.


> Ah, this should work fine. There is always the possibility of a

> thread safety issues somewhere in the code which might need to be fixed > but I assume this approach is fine and use it myself without apparent

> problems.
> Sorry for misunderstanding.

Best regards,

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