This is presently only applicable on Mac OS X (it is ignored on other platforms). If you link the dependency-free version of the static PLUSNative library for Mac OS X with your own builds of libcurl and OpenSSL, and you configure libcurl to use OpenSSL [--with-openssl] (not DarwinSSL [--with-darwinssl]) for encrypted transmissions, then you may need specify this global flag when calling SK_ApiContextInitialize in order to set the SSL certificate bundle path.