Using system() with gnuplot in qt

[ChrisW67]

I can see three options:

• Write your gnuplot commands to a temporary file and execute:

  system("gnuplot <tempfilename");

  system("gnuplot <tempfilename");

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  You can use mkstemp (3) or QTemporaryFile to get a safe temporary file.
• Open gnuplot using QProcess and write your gnuplot commands to the sub-process input stream that QProcess provides.
• popen (3) gnuplot and use the FILE handle returned to write your gnuplot commands before pclose (3)