ihuFetchTagCache

Use this function to fetch a current set of tags and properties from the Historian server and place them into an API cache for subsequent queries, such as ihuGetNumericTagPropertyByTagname.

Prototype

ihuFetchTagCache {
  in long serverhandle,
  in MSO Char * tagmask,
  out int * NumTagsFound
};

Remarks

The function retrieves properties for each tag received.

There is a single API tag cache. You must free the previous tag cache before you do another fetch from the same or a different server. Keep this in mind when you access the tag cache from multiple threads in the same application. Alternatively, use the ihuCreateTagCacheContext and ihuFetchTagCacheEx2 or ihuFetchTagCacheEx3 functions.

Returns

• ihuSTATUS_OK
• ihuSTATUS_INVALID_PARAMETER