Write to file bug (or feature)

[Ulf]

Hi!

I'm having problem with logging data to a file in the background. LabVIEW halts at "File Open" if the user is using LabVIEW file browser at the same time. I have found a way around this, but I don't now why it works? I have attached a simple test program for the "bug". Run the VI and press "browse"-button, look at the two indicators "Loop1" and "Loop2".

Best regard Ulf

FileOpenProblem.vi

[Ton Plomp]

It's a feature.

A nasty one, but it only halts VIs in the user thread.

Ton

[jgcode]

Hi!

I'm having problem with logging data to a file in the background. LabVIEW halts at "File Open" if the user is using LabVIEW file browser at the same time. I have found a way around this, but I don't now why it works? I have attached a simple test program for the "bug". Run the VI and press "browse"-button, look at the two indicators "Loop1" and "Loop2".

Best regard Ulf

I ran this on Windows 7 and it works fine.

Both loops continued to increment the index with the browse dialog open.

I even switched execution to user interface and it worked fine.

Is this feature OS dependent?

[Ulf]

I ran this on Windows 7 and it works fine.

Both loops continued to increment the index with the browse dialog open.

I even switched execution to user interface and it worked fine.

Is this feature OS dependent?

I'm running on XP LV8.5 & LV8.6

//Ulf

[jgcode]

I'm running on XP LV8.5 & LV8.6

//Ulf

I forgot to say LV2009 for me.

[Rolf Kalbermatter]

I forgot to say LV2009 for me.

I would guess that this is more important than the fact that it is Windows 7.

Apparently someone put some love into the File IO C code and removed a global somewhere in the Open File function that prevented that function from being called as a thread-agnostic function, so the File dialog, which has to run in the UI thread since it does UI , can't block it anymore.

[ssingh]

Hi!

I'm having problem with logging data to a file in the background. LabVIEW halts at "File Open" if the user is using LabVIEW file browser at the same time. I have found a way around this, but I don't now why it works? I have attached a simple test program for the "bug". Run the VI and press "browse"-button, look at the two indicators "Loop1" and "Loop2".

Best regard Ulf

Loops working Ok for me even when browse is pressed on Win XP SP2 LabView 2009

[Raymond]

I'm seeing the same problem...

So, there's no way around it?

[Rolf Kalbermatter]

I'm seeing the same problem...

So, there's no way around it?

Of course there is! Use a recent LabVIEW version and of course don't use functions that are synchronized through the UI thread. That includes all VIs itself set to run in the UI thread but also just about every LabVIEW VI server function including Property Nodes and Methods.And everything else that will put up a UI screen such as a dialog or similar.

[Raymond]

Of course there is! Use a recent LabVIEW version and of course don't use functions that are synchronized through the UI thread. That includes all VIs itself set to run in the UI thread but also just about every LabVIEW VI server function including Property Nodes and Methods.And everything else that will put up a UI screen such as a dialog or similar.

Thanks for your reply, but I'm not sure if I understand what you suggest... Are you saying that I should change some settings in 'VI properties' for all sub-VIs?