Based on the error logs, it could be here, since this is the only call to curl_easy_strerror() that is not prefixed with some identifying string.
But that is not the case. It's actually
(I changed how BESError objects are logged when Verbose logging is turned on.)
This is error comes from:
I will change the BESDEBUG lines so that we can track lock/unlock operations and re-run the tests.