Writing to a file using labview

Question

hello,
so i wrote this vi to write some data to a text file and that part works correctly.
the problem i'm having is that, it doesn't append to the file. so for each data point that it writes it requires a new file.
in otherwords, if i need to write 10 data points the program prompts each time for 10 different file names.
how do i resolve this so that the program will write all the 10 data points to one file, by appending each time.
e.g. data points: 29.5, 34.2, 21.34, 543.2 ... etc
i want something like this:
29.5
34.2
21.34
543.2
etc
thanks
-r

Answer 1

If the path is correctly wired, it should not prompt you for another file. Make sure you wire the path to a shift register so it is available the next time the "write charaters ..." is called.
You can do the "exception" in many ways. Some examples:
--Check if the file exists, and if so, append.
--Use a shift register initialized by "false", then wire it to the append terminal. Feed a "true" to the shift register on the right.
However, you should consider using some of the lower level file I/O and open the file only once, then keep writing data and close it only at the end. The high-level "write characters to file" would need to do a lot of extra work because whenever it is called it opens the file, writes/appends data, then
closes the file again.
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