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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Chuck,<o:p></o:p></span></p>
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color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>You should make your own thread-safe wrapper class(es) for using
GEOS in my opinion. That’s what I do and it works great. If you need high
performance on a server then create a thread pool manager with a semaphore
around a pool of your wrapper classes.<o:p></o:p></span></p>
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color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Martin</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p></o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
geos-devel-bounces@lists.osgeo.org [mailto:geos-devel-bounces@lists.osgeo.org] <b>On
Behalf Of </b>Charles Thibert<br>
<b>Sent:</b> Friday, August 22, 2008 11:45 AM<br>
<b>To:</b> geos-devel@lists.osgeo.org<br>
<b>Subject:</b> [geos-devel] CAPI Thread Safety<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p style='margin-bottom:12.0pt'><span style='font-size:10.0pt'>Hello,<br>
<br>
Little introduction first. I'm working for Ingres with Andrew Ross on<br>
the new Ingres geospatial extensions. Ingres is planning to re-use the<br>
GEOS library through the CAPI. I've been looking over it to 1)<br>
familiarize myself with the code and 2) to identify possible thread<br>
safety issues.<br>
<br>
There are two things that jump out at me. 1) The error/notification<br>
handlers are definitely not thread safe unless each thread can use the<br>
same handlers. 2) The geometryFactory worries me. It seems like it
may<br>
be thread safe, such that it creates new objects only. I'm looking for<br>
some expert opinions on that.<br>
<br>
I've tried to search the archives of the mailing list but the .gz files<br>
don't seem to work for me and the online browsing isn't search-able, so<br>
forgive me if this questions been asked before... Are there any current<br>
plans/work being done to make the CAPI more thread safe?<br>
<br>
Thanks,<br>
Chuck Thibert</span><o:p></o:p></p>
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