Xerces-C is the C++ XML Parser from the Apache Software Foundation. It is used for all XML processing in OpenSAML and Shibboleth.
Project Website: http://xerces.apache.org/xerces-c/
Versions of OpenSAML prior to 2.2 (and Shibboleth 2.2) support Xerces the 2.x release, 2.8.0 being the suggested version. As of OpenSAML 2.2, Xerces 3.x is also now supported, and is the suggested version to use going forward.
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