批处理中为何已经成功的程序只是变更输入路径就导致后续出错？

Question

原代码为：
cd. >C:\Users\DELL\Pictures\list.txt
cd. >C:\Users\DELL\Pictures\list1.txt
for /f "delims=" %%n in ('dir /b /s Z:\二级网巡\二级网巡照片\2020年\3月') do echo %%n>>C:\Users\DELL\Pictures\list.txt
for /f "delims=" %%i in (C:\Users\DELL\Pictures\list.txt) do (
echo %%i|findstr ".jpg">>C:\Users\DELL\Pictures\list1.txt
)
pause
这个程序执行没有问题

一旦修改为：
cd. >C:\Users\DELL\Pictures\list.txt
cd. >C:\Users\DELL\Pictures\list1.txt
set /p path=请输入需要查找.jpg图片的目标文件夹
for /f "delims=" %%n in ('dir /b /s %path%') do echo %%n>>C:\Users\DELL\Pictures\list.txt
for /f "delims=" %%i in (C:\Users\DELL\Pictures\list.txt) do (
echo %%i|findstr ".jpg">>C:\Users\DELL\Pictures\list1.txt
)
pause
运行后
for /f "delims=" %%i in (C:\Users\DELL\Pictures\list.txt) do (
echo %%i|findstr ".jpg">>C:\Users\DELL\Pictures\list1.txt
)
就无法执行命令
结果是list.txt内容完整
但是list1.txt就是空白文件

请问到底是什么原因？

---

已找到原因
path是系统变量 换成其他变量作为输入赋值变量就可以运行了

Answer 1

https://blog.csdn.net/weixin_30485291/article/details/95495359