Send a Variable to a command line processes in php?
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I don't know if it is possible but here it is, i am trying to send a variable to a command line processes that i have opened. 

      $command = "cd FilePAth;";
      $command .= 'export PATH=$PATH:`pwd`;';
      $command .="Compiler -lotsaspace /../var/www/testGraduationProject1/public/Hume2Compiler/examples/transpose14.hume 2> test.txt;" . '> /dev/null 2>&1 & echo $!;';
      $test = exec($command, $op);

in the variable `$test` i will get the PID could i use this PID and send a variable to that processes (The processes will be open to get variables)  ? 