private ProcessResult exec(List<String> argList,boolean strictErr) throws Exception {
        for(String x:argList) {
            System.out.print(x);
            System.out.print(' ');
        }
        System.out.println("");
        ProcessResult result=shell.exec(argList.toArray(new String[argList.size()]));
        if(strictErr) {
            if(result.getReturnCode()!=0)
                if(result.getStdErr().trim().length()>0||
                   result.getStdOut().trim().length()>0)
                    throw new RuntimeException(result.toString());
        } else
            if(result.getStdErr().trim().length()>0&&result.getReturnCode()!=0)
                throw new RuntimeException(result.toString());
        return result;
    }