src/Operation.php
private function runCommandForNix($file)
    {
        $cmd = "php {$file} ";

        if (!$this->logging) {
            $cmd .= '> /dev/null 2>&1 & echo $!';
        } else {
            $cmd .= "> {$this->logging} & echo $!";
        }

        return (int) shell_exec($cmd);
    }
private function runCommandForNix($file)
    {
        $cmd = "php {$file} ";

        if (!$this->logging) {
            $cmd .= '> /dev/null 2>&1 & echo $!';
        } else {
            $cmd .= "> {$this->logging} & echo $!";
        }

        return (int) shell_exec($cmd);
    }
Execute the shell process for the *nix platform.

@param string $file The absolute path to the executing file.

@return void