check_once_cc_ccache_get_credentials_version
check_once_cc_ccache_get_credentials_version(ccache, cc_credentials_v5, ccNoError, "v5 creds");
cc_int32 check_once_cc_ccache_get_credentials_version(cc_ccache_t ccache, cc_uint32 expected_cred_vers, cc_int32 expected_err, const char *description);