quanser.communications.stream.send_single

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Sends a 32-bit floating-point number over a stream.

Syntax

[items_sent, would_block] = stream.send_single(value)

Description

This function writes a single 32-bit real number to the stream buffer. It attempts to store the 32-bit real number in the stream buffer. If there is enough room available in the stream buffer then it stores the data in the buffer and returns immediately. The data is not written to the actual communication channel until the stream is flushed using flush or there is no more room available in the stream buffer. If an error occurs, then it issues an error message. If the connection is closed it is considered an error condition.

If quanser.communications.stream.listen or quanser.communications.stream.connect was called with the non-blocking flag set to false (0), then this function may block attempting to flush the stream buffer. All the data will be consumed and the total number of elements sent is returned. Some of the data may remain in the stream buffer and not be sent until the next time flush is called or there is no more room available in the stream buffer. If an error occurs then an error is issued and the stream should be closed.

If quanser.communications.stream.listen or quanser.communications.stream.connect was called with the non-blocking flag set to true (1), then this function does not block. It returns the number of elements sent successfully, which will be 1. If no elements could be sent without blocking, then would_block is set to true (1). If an error occurs then an error is issued and the stream should be closed.

This operation is not valid on listening streams created using quanser.communications.stream.listen.

Parameters

stream

Stream handle returned by quanser.communications.stream.connect or accept.

value

The 32-bit real number to send. Any numeric datatype may be used but the value will be cast to a single prior to writing the data to the stream.

Outputs

items_sent

The number of items actually written to the stream buffer, which may be 0 for non-blocking streams. For blocking streams, a value of 0 is never returned.

would_block

Whether the function would have blocked. Always false for blocking streams.

Examples

num_items = stream.send_single(3.14);    % Send the 32-bit real number 3.14