[Proj] PROJ.4 and OpenMP

[Even Rouault]

Le jeudi 02 juillet 2015 20:07:49, support at mnspoint.com a écrit :
> Hello Jose,
> 
> if I remember correctly all what Frank W. did was that he added a single
> line containing a mutex object to the source code .. that was all. 

> You
> might want to run a file comparsion for the first "multithreaded" proj.4
> and the version before it .. but just a single line was added I assume?!
> 
> So most likely what you should do is to use that mutex object .. there
> should be lot of examples about how to use a mutex objects in the
> network.

Janne,

Sorry but I must correct your above statement, since that's just 
misinformation and rather offending regarding FrankW's efforts in that area.

The changes in proj to make it thread-safe involved touching a lot of files, 
not just one. Just look at the first commit to add thread-safety : 
https://github.com/OSGeo/proj.4/commit/ec678c07c2acb83da8a2187c541b8a2e452dec4b 
And there have been several afterwards.

If you use the "new" proj API that accept a projCtx argument, no need for a 
mutex.

Even
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