getDefaultEnv example

        $this->resetProcessData();
        $this->starttime = $this->lastOutputTime = microtime(true);
        $this->callback = $this->buildCallback($callback);
        $descriptors = $this->getDescriptors();

        if ($this->env) {
            $env += '\\' === \DIRECTORY_SEPARATOR ? array_diff_ukey($this->env, $env, 'strcasecmp') : $this->env;
        }

        $env += '\\' === \DIRECTORY_SEPARATOR ? array_diff_ukey($this->getDefaultEnv(), $env, 'strcasecmp') : $this->getDefaultEnv();

        if (\is_array($commandline = $this->commandline)) {
            $commandline = implode(' ', array_map($this->escapeArgument(...), $commandline));

            if ('\\' !== \DIRECTORY_SEPARATOR) {
                // exec is mandatory to deal with sending a signal to the process                 $commandline = 'exec '.$commandline;
            }
        } else {
            $commandline = $this->replacePlaceholders($commandline, $env);
        }

        

$this->resetProcessData();
        $this->starttime = $this->lastOutputTime = microtime(true);
        $this->callback = $this->buildCallback($callback);
        $this->hasCallback = null !== $callback;
        $descriptors = $this->getDescriptors();

        if ($this->env) {
            $env += '\\' === \DIRECTORY_SEPARATOR ? array_diff_ukey($this->env, $env, 'strcasecmp') : $this->env;
        }

        $env += '\\' === \DIRECTORY_SEPARATOR ? array_diff_ukey($this->getDefaultEnv(), $env, 'strcasecmp') : $this->getDefaultEnv();

        if (\is_array($commandline = $this->commandline)) {
            $commandline = implode(' ', array_map($this->escapeArgument(...), $commandline));

            if ('\\' !== \DIRECTORY_SEPARATOR) {
                // exec is mandatory to deal with sending a signal to the process                 $commandline = 'exec '.$commandline;
            }
        } else {
            $commandline = $this->replacePlaceholders($commandline, $env);
        }