TSHttpTxnCacheLookupStatusGet error

["Walsh, Peter" <Pe...@disney.com>]

Hello,
Has anyone had success using the method TSHttpTxnCacheLookupStatusGet
(http://trafficserver.apache.org/docs/v2/sdk/HTTPTransactionFunctions.html#
INKHttpTxnCacheLookupStatusGet) from within the hook
TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK?

I'm interested in programmatically retrieving the status of the cache
lookup in a plugin and I've been attempting to use the
TSHttpTxnCacheLookupStatusGet method but it appears to always return in
error.

Here's an outline of the steps I've taken:
- Register for TS_HTTP_CACHE_LOOKUP_COMPLETE_HOOK with TSHttpTxnHookAdd
after TS_EVENT_HTTP_TXN_START.
- Look for the event TS_EVENT_HTTP_CACHE_LOOKUP_COMPLETE in my handler
- then call to TSHttpTxnCacheLookupStatusGet(txnp, &lookup_status) to
retrieve the cache lookup status.

However I can see in my squid.log file what the lookup status should be so
I know a cache lookup is happening.

Any thoughts?

Thanks,
Pete