nasm - What does mov cx, 02001Q mean in assembly

Question

I'm doing an analysis of the shellcode found at http://www.shell-storm.org/shellcode/files/shellcode-211.php

I was wondering what this particular instruction does:

mov cx, 02001Q

I know it moves a value into cx, but I'm not sure what the Q stands for.

Answer 1

来自NASM 文档；

NASM 允许您以多种方式以各种数字基数指定数字：您可以为十六进制、十进制、八进制和二进制分别添加 H 或 X、D 或 T、Q 或 O 和 B 或 Y 后缀

换句话说，02001Q表示 2001 八进制。