error when indicator connected

[M_Peeker]

Hi all!

I've run into something weird with the application property "Printing -> Available Printers". Using LV 8.5.1 on Linux, i get error 53 ("Manager call not supported.") if i have an indicator or any other node connected to the Printers output of the property node. However, if I do not have an indicator connected LV does not report an error.

Now to some questions:

1. Why can I not see my printers?

2. Why do I get an error only if a node is connected to the property node output?

3. Is this a Linux problem or does it behave similarly on other platforms?

Thanks

//Martin

[muks]

Most probably your manager call is not supported.Have a look at this

[M_Peeker]

I'm not really sure I understand what is meant by a manager call. In my case I want to see which printers are connected to my system using the application properties. This should be a direct link between LV and the operating system I believe, so no addons should be needed. Could it be something missing in my Linux distribution (rather new to Linux)? And again, why does the error behave like it does?

[muks]

So is this the error u r getting?

 

[muks]

Cross reference

[James_McN]

Hi,

I'm afraid that property node is only available in Windows as it is something that will have to talk to the operating system and so will be dependent.  I do wonder whether you can do someting similar using library calls or something of that nature in Linux.  Perhaps go to the CUPS website and see if they can offer any help and I will have a quick look and see if anything jumps out at me.

Regards, 

[M_Peeker]

James:

Thanks for your reply. Is there a way for me to know which properties aren't available in Linux? I'm a noob with linux so I appreciate every single bit of help I could get in these matters. I will check the CUPS site and see if I understand what they are talking about.

Muks:

Yes, that is the error I get although with a different origin (it seems the error is rather generic):

Error 53 occurred at Property Node (arg 1) in PrinterError.vi

Possible reason(s):

LabVIEW:  Manager call not supported.

Property Name: Printing:Available Printers

Property Name: Printing:Available Printers 

[James_McN]

Hi Again,

LabVIEW help should give you details of whether a property needs certain situations to work so if you go onto context help on your property node and click detailed help it will show you there.

Found the following site that details the CUPS API functions that you can call from their libraries so it appears possible.  I am just trying to find an example on how to use the structure inputs using clusters as many of the functions use structures for printer details.

Regards,

[TCPlomp]

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M_Peeker wrote:

2. Why do I get an error only if a node is connected to the property node output?

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Well that is a compiler optimization, code that has no output will not be executed. So if you have no node connected, LabVIEW will assume you don't need the information, and LabVIEW will not execute the node.

Ton