title: connect c++ file and gnuplot and plot automatically after execution
body: <p>is there any way (instruction) to connect <code>gnuplot</code> to C++ code, so it can automatically plot file whenever the execution of C++ file ends, without passing through traditional plotting steps in gnuplot: opening gnuplot, etc.</p>
  
  <p>I'm looking if there are any instruction that can call <code>gnuplot</code> plotting option from C++ code so it will plot file right after the compilation ends.</p>