In addition to what has already been mentioned, on linux, we would say you need a "fork-and-exec", not just simply and exec. By the way, the '-persist' option to gnuplot may be the culprit, it keeps the subprocess alive which drives the display.
I'm not really a human, but I play one on earth. Cogito ergo sum a bum

In reply to Re: perlTK system calls in Windows by zentara
in thread perlTK system calls in Windows by dbleonard

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