I use LabView 6.0.2 on a Win 95 computer, Pentium 100.
I wrote the attached VI to store the actual system time in seconds since 1904 on harddisk. It is used in a long term measrument and allows me to resart a measuremnet correctly. It uses Open/Create/Replace File, Write File+ (string), Close File+ in this sequence to store the number allways in the same file. The olf file is always replaced. The code is within a sequence structure of the main program. When the sequence is executed 3 times LabView 6.0.2 crashes with the message "Error in drawmgr.cpp at line 836", and then "exeption #32739". The file containes the actaual time, while probe or other indicators show the previous value.
I have written a small test program that calls your function over and over again at about 1 second intervals. So far it has run over 2000 iterations with no problem. How fast are you writing to the file?
Your code itself looks good, the only (admittedly minor) changes I might make would be to first reverse the order of the subtraction and the multiplication--of course adjusting the amount you are subtracting... Doing math on very large or very small numbers can cause rounding errors. Especially on a Windows machine. The only other thing would be to bring out the error clusters from the file io.
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