Function ziAPIGetValueAsPollData#

ZIResult_enum ziAPIGetValueAsPollData(ZIConnection conn, const char *path)#

triggers a value request, which will be given back on the poll event queue

Use this function to receive the value of one or more nodes as one or more events using ziAPIPollDataEx, even when the node is not subscribed or no value change has occurred.

See Data Handling for an example

See also

ziAPISubscribe, ziAPIUnSubscribe, ziAPIPollDataEx

Parameters:

  • conn – [in] Pointer to the ZIConnection with which the value should be retrieved

  • path – [in] Path to the Node holding the value. Note: Wildcards and paths referring to streamimg nodes are not permitted.

Returns:

  • ZI_INFO_SUCCESS on success

  • ZI_ERROR_CONNECTION when the connection is invalid (not connected) or when a communication error occurred

  • ZI_ERROR_LENGTH if the Path’s Length exceeds MAX_PATH_LEN or the length of the char-buffer for the nodes given by MaxLen is too small for all elements

  • ZI_ERROR_COMMAND on an incorrect answer of the server

  • ZI_ERROR_SERVER_INTERNAL if an internal error occurred in the Data Server

  • ZI_WARNING_NOTFOUND if the given path could not be resolved or no value is attached to the node

  • ZI_ERROR_TIMEOUT when communication timed out

  • Other return codes may also be returned, for a detailed error message use ziAPIGetLastError.