Access to data during aquisition | LabJack
 

Access to data during aquisition

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dh53
dh53's picture
Access to data during aquisition

I would like to collect data over several days but have access to that data during the time my Labjack is actively collecting data. I do not need frequent updates, something like once per day.  I understand I can log data to a file using LJLogUD.  My question is what happens if I have that file open, or even if I am making a copy of that file such that the operating system (Windows 7 or Windows 10) reports the file is in use when the U6 tries to write to that file?  Do I lose the data that was trying to be written while the file is open?  Or does a file error create bigger problems?  Or a new log file?

I should mention the labjack will be writing to a local hard drive and I want to peek at the data from a different loaction on a LAN so I can't easily pause the data collection.

swbarlow
swbarlow's picture
dh53,

dh53,

There are so many factors involved in how you get your data, API, language etc...( and I could go on and on here).  I'm going to assume most of us, program our stuff in various languages and it is the responsibility of the programmer to figure out the storage. For instance I use a database , SQL server or what not and dump from my programming to the database. That is up to the programmer, its not really a function of the device or the API / language  that you choose to use.

Without further information I can't really tell you much, other than I have been using the units for years, but they are a devices. How you choose to retrieve whatever information , or store it, is on your end. Its not a respoonsibility of the device.

Scott

 

 

 

 

 

 

 

 

LabJack Support
labjack support's picture
Most of our customers are

Most of our customers are writing their own software with our great libraries, so what you say is true Scott, but I can comment specifically on LJLogUD.exe which is a Windows executable we provide:

https://labjack.com/support/u6-software-options

LJLogUD opens a new file to log data, and keeps that file open until it is done with it.  I just did a test on my machine where I started logging in LJLogUD, and then opened the current log file in a text editor.  It showed all data up to the point where I opened it and stayed that way.  When I closed and reopened it did the same but now showed data that was logged while I had the file open.  It seems to me that since the file is held open by LJLogUD, my text editor is opening it in read-only mode or opening some sort of copy of the file.  Anyway, it seems to behave in a way that is good for you dh53, but I would do a similar test on your machine.