Well, the start point would be - gnuplot is doing exactly what you ask it. You fork your code, then send the content of DATA to gnuplot, and then exit. It only does that once, because you only ask it to do it once.

In doing so, you create a bit of a race condition, as to whether your gnuplot will read your data before you've finished generating it

But either way - your code sits in a loop generating more data, but you never tell gnuplot to process it again.

In reply to Re: fork spawn write background problem by Preceptor
in thread fork spawn write background problem by grasshopper!!!

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