How to read data from the cache in c++

Question

I am using a toolkit to develop client and server , which contains "WriteItems" function. Initially server creates some items and client reads these items. Then client make some changes on this items.The "WriteItems" method will be called every time the client changes the items. When "WriteItems" function is called, data will be copied to the cache by the toolkit. Now, I have to display this data from cache.

Since I am newbie and searched in the web to read data from cache, i could not find appropriate way of solution. I hope that i can get some suggestion.

Answer 1

The OPC client can issue a SyncRead or AsyncRead. When doing so, you specify whether the requested data should come from the cache or from the device. If you specify cache, the OPC server should return whatever value and quality it currently has in its cache for the requested items.