Cascade Historian™ : Version 6.4
	Dynamic Library Functions

`hist_buffer_id_length`

hist_buffer_id_length — queries for the number of X-Y pairs.

Syntax

hist_buffer_id_length (hist_task, queryid)

Parameters

hist_task

The task object corresponding to the Cascade Historian. A task object is created by a call to the Gamma function locate_task, as follows:

hist_task = locate_task ("tfrc/histdb", nil);

queryid

The reference number for the result of a query made on the Cascade Historian using the hist_interpolate function or the interpolate command.

Returns

The number of X-Y data pairs, an integer-valued number.

Description

This function queries the Cascade Historian for the number of X-Y pairs (the buffer length) in the result of an interpolate query. This value can be used to request the buffer from the Cascade Historian with the hist_buffer_id_read function.

This function corresponds in part to the bufferIdLength command and the Cogent C API function HI_BufferIDLength.

Example

See the example for hist_exchange_buffer.


hist_buffer_id_destroy		hist_buffer_id_read

hist_buffer_id_length