Read from text file vi won't read file...

I am very new to LV programming so I hope you forgive any stupid mistakes I am making.   I am using Ver. 8.2 on an XP machine.
I have a small program that stores small data sets in text files and can update them individually or read and update them all sequentially, sending the data out a USB device.   Currently I am just using two data sets, each in their own small text file. The delimiter is two commas ",,".
The program works fine as written when run in the regular programming environment. I noticed, however, as soon as I built it into a project that the one function where it would read each file sequentially to update both files the read from text file vi would return an empty data set, resulting in blank values being written back into the file. I read and rewrite the values back to the text file to place the one updated field (price) in it'sproper place. Each small text file is identified and named with a 4 digit number "ID".   I built it twce, and get the same result. I also built it into an installer and unfortunately the bug travelled into the installation as well.
Here is the overall program code in question:
Here is the reading and parsing subvi:
If you have any idea at all what could cause this I would really appreciate it!
Solved!
Go to Solution.

Hi Kiauma,
Dennis beat me to it, but here goes my two cents:
First of all, it's great to see that you're using error handling - that should make troubleshooting a lot easier. By any chance, have you observed error 7 when you try to read your files and get an empty data set? (You've probably seen that error before - it means the file wasn't found)
If you're seeing that error, the issue probably has something to do with this:
Relative paths differ in an executable. This knowledge base document sums it up pretty well. To make matters more confusing, if you ever upgrade to LabVIEW 2009 the whole scheme changes. Also, because an installer contains the executable, building the installer will always yield the same results.
Lastly, instead of parsing each set of commas using the "match pattern" function, there's a function called "spreadsheet string to array" (also on the string palette) that does exactly what you're doing, except with one function:
I hope this is helpful...
Jim

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From the LabVIEW Help: http://zone.ni.com/reference/en-XX/help/371361G-01/glang/array_to_cluster/
Converts a 1D array to a cluster of elements of the same type as the array elements. Right-click the function and select Cluster Size from the shortcut menu to set the number of elements in the cluster.
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Ohmy, thanks altenbach. oh yeah i forgot about those sub VIs. will upload them now. Was rather demoralized after reading the comments and really struck me on how weak i'm at on labview really hope to get this done. But of course i have to study through and see how it works. Actually i am going to replace those 'signal generators sub vi' with ThoughtTechonology's sample code so i can obtain data waveforms real-time using Electrocardiography (ECG) ,Electromyography (EMG ) and Electroencephalography (EEG) hopefully i can find out how to connect the sample code.
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Hello,
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I have another solution, the EOF works with this one.
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you only want to say that if it's in line mode and cnt > 256 (BUFINCR) cnt = BUFINCR
the next time cnt is the value of the bytes that are not read yet, so the old value minus the line (until CR LF) or if cnt (256) is reached.
with this solution the program does not try to allocate the whole file but for the max of 256.
in CCGByteStreamFileSupprt.c row 705
if(linemode && (cnt>BUFINCR)){
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don't use the count input when using the vi in line mode. count does not make sense, cnt will be the total file size. also the output will be an array.
linemode seems to be the value of the file size but I checked this and it is just 0 or 1, so this is good
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?hein??
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Here is what I get from Context Help on the Read From Text File:
Read from Text File
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Humm.
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