AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2000.01.30 01:02 "libtiff in a M$ Windows Visual C++ 5.0 DLL for Borland Delphi 3,4,5", by Joris Van Damme
2000.01.31 14:46 "Re: libtiff in a M$ Windows Visual C++ 5.0 DLL for Borland Delphi 3,4,5", by Bruce Cameron
2000.01.31 15:05 "Re: libtiff in a M$ Windows Visual C++ 5.0 DLL for Borland Delphi 3,4,5", by Scott Wagner
2000.01.31 15:02 "Re: libtiff in a M$ Windows Visual C++ 5.0 DLL for Borland Delphi 3,4,5", by Frank Warmerdam
2000.01.31 18:29 "Re: Threadsafe MSVC implementation of LibTiff", by Scott Wagner
2000.02.05 01:06 "Re: threadsafety of libtiff 3.5.4?", by Frank Warmerdam

2000.02.05 01:06 "Re: threadsafety of libtiff 3.5.4?", by Frank Warmerdam

Joshua Blatt wrote:
>
> Can anyone tell me whether the 3.5.4 library is threadsafe? Thanks,
> Josh

Joshua,

Earlier this week Scott Wagner said:

>LibTiff (including its Windows DLL incarnation) is almost(!) reentrant. >That is, the only pieces which are non-reentrant are the pieces which set >up the warning and error handlers. For most uses, this is OK - set up your >warning and error handlers at initialization; then you can handle multiple >images with multiple TIFF handles without collisions.

The build of libtiff which I use is built from source by me - not Frank Warmerdam's build. Mine is a threadsafe DLL, and I call it from multithreaded applications. My experience is that (at least with my Borland compiler) the default C runtime library code selected is the more compact single-thread version; I have to select the multi-threaded CRTL as an option. This is probably true of VC++ as well.

Frank, can you comment on this?

Everything he says makes sense to me. So take care to build it yourself against a multi-threaded run time library, and don't try to access the _same_ TIFF file from different threads concurrently.

Best regards,

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