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Connection Responsiveness:Information Method

LabVIEW 2013 Help

Edition Date: June 2013

Part Number: 371361K-01

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Short Name: Conn Responsive.Info

Requires: Base Development System

Class: Application Methods

To Use: Create a method.

Gets and sets how often LabVIEW checks if a VI Server connection is responsive.

Set the PingDelay and PingTimeout parameters of this method to configure how LabVIEW checks the connection. If LabVIEW does not receive a message in the time you specify in PingDelay, LabVIEW sends a query to prompt the VI Server network connection for a message. After sending the query, if LabVIEW does not receive a message in the time you specified in PingTimeout, LabVIEW considers the connection unresponsive. Then, all VIs and functions waiting on the connection return network connection error code 1130.

For example, if you set PingDelay to 3000 and PingTimeout to 1000, LabVIEW sends a query to verify the status of the VI Server network connection every time 3 seconds elapse without LabVIEW receiving a message over the connection. If LabVIEW does not receive a reply from the network, LabVIEW waits 1 second before all VIs and functions waiting on the connection return network connection error 1130, which you can handle on the block diagram.

Default for PingDelay and PingTimeout is 10,000 ms, which means LabVIEW checks the connection every 10 seconds and waits up to 10 seconds for the connection to respond.

Note  If a network operation times out according to the timeout value you specify in PingTimeout, LabVIEW considers the connection unresponsive but does not close the connection. All current and future calls waiting on the connection return a connection error. LabVIEW does not send another message to query the connection status until LabVIEW considers the connection responsive again. A connection becomes responsive again when LabVIEW receives a message over the connection.

Parameters

Data typeNameRequiredDescription
PingDelayNoSpecifies how long between queries LabVIEW waits, in milliseconds. If you specify a value of –1 (infinity) LabVIEW does not check the connection unless you use the Connection Responsiveness:Check method. If you want LabVIEW to check the connection, you must set PingDelay to a positive number or use the Connection Responsiveness:Check method.
PrevPingDelayNoPingDelay in milliseconds you previously specified.
PingTimeoutNoSpecifies how long in milliseconds before LabVIEW times out after LabVIEW sends a query to prompt the VI Server network connection for a message. If a timeout occurs, all VIs and functions waiting on the connection return a connection unresponsive error.
PrevPingTimeoutNoPingTimeout in milliseconds you previously specified.

Remarks

The following table lists the characteristics of this method.

Data typeNo return value
Available in Run-Time EngineYes (Read/Write)
Available in Real-Time Operating SystemYes
Remote access allowedYes

 

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