Returns the element at the front of the queue without removing the element from the queue.
If the queue becomes invalid because the queue reference is released, this node stops waiting and returns an error.
A reference to a queue.
The number of milliseconds that the node waits for an element to become available in the queue if the queue is empty.
If an element becomes available in the queue during the wait, the node removes and returns the element and does not time out.
Default: -1 — The node never times out.
Error conditions that occur before this node runs. Unlike most nodes, this node runs normally even if an error occurs before this node runs.
Default: no error
Reference to the queue.
A copy of the element at the front of the queue.
The data type of this output changes to match the data type of the queue elements.
A Boolean value that indicates whether an element became available in the queue before the node timed out or if an error occurred.
|True||An element did not become available before the node timed out or this node generated an error.|
|False||An element did become available before the node timed out or an error occurred before this node executed.|
The node produces this output according to standard error behavior.
This node can return the following error codes.
|1122||The reference became invalid while the node was waiting for it.|
Standard Error Behavior
Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.
|error in does not contain an error||error in contains an error|
|If no error occurred before the node runs, the node begins execution normally.
If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.
|If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.|
Where This Node Can Run:
Desktop OS: Windows
FPGA: Not supported
Web Server: Supported in VIs that run in a web application