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How to read data from a file that is already open by another program

Hey..

I have made IV, where I'm trying to read data from a log file, that is being updated by another program while my IV runs.
To be clear, this program writes data continuously to this file and I want to read from the file in LV at the same time.

 

The problem is that LV reports an error when I'm trying to read the log file, even if I use to "read only" mode.
I believe that the program that is producing the file, have some kind of lock on the file. I have tryed to copy the file and then reading from the copied file, but LV throws already an error when I try to copy the file.

 

Has anyone tryed this, and found a solution.?

 

Additional info: The program that produces the file is STM Studio 

 

Best Regards
Allan

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Hi Alha,

 

when that file is locked by the other program you can't do anything about that - apart from quitting that other program. Probably this isn't an option to you…

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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http://www.howtogeek.com/howto/windows-vista/backupcopy-files-that-are-in-use-or-locked-in-windows/

This is probably worth a try. We all have to jump through hoops provided by Microsoft from time to time!

I know I have not exactly given you a working solution but it may get you going

All the best
Michael
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Hey Michael

 

Thanks for the proposal..

 

It worked, but the program (hobocopy) takes to long, to copy the file,

about 10 sec. and I want to do it much faster, less then 10ms.

 

/Allan

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A friend of mine suggested tail, a linux thing. I found a possible solution here:

http://tailforwin32.sourceforge.net

Let me know how you get on here. 10ms is a tough one. I dont think a faster drive like an ssd will help get close, there is the possibility of a simulated ram drive but I guess could be problematic. Tail sounds ideal so best of luck.
Michael
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