China DOS Union

@echo off&setlocal enabledelayedexpansion
for /f "usebackq tokens=2 delims=:" %%i in (`ipconfig ^| find "Default Gateway"`) do set gw=%%i
for /f "usebackq tokens=2 delims= " %%i in (`arp -a ^| findstr "\<!gw!\>"`) do echo %%i
pause

Why can getting the MAC address of the gateway work when using `findstr "\<10.0.0.1\>"`
but not when using the delayed variable !gw!?

[ Last edited by jun19841 on 2010-12-6 at 14:58 ]

Look at my place http://www.cn-dos.net/forum/viewthread.php?tid=52933&fpage=2
The explanation on floor 11!~
It's because you have already brought the space in when setting gw=%%i
The result is "space + Default Gateway"
The correct way should be written like this:

@echo off

for /f "tokens=2 delims=:" %%i in (`ipconfig ^| find "Default Gateway"`) do set gw=%%i

for /f "tokens=2 delims= " %%i in (`arp -a ^| findstr "\<%gw:~1%\>"`) do echo %%i

pause

%gw:~1% is used to remove the leading space that was brought in

Thanks to Hanyeguxing for the guidance, I've learned it~

Originally posted by Hanyeguxing at 2010-12-6 15:12:
Check the explanation on floor 11 of http://www.cn-dos.net/forum/viewthread.php?tid=52933&fpage=2!~
You already included the space when you did set gw=%%i
The result is "space + Default Gateway ...

Hmm, inserting call can also be used to call, learned~

for /f "usebackq tokens=2 delims= " %%i in (`arp -a ^| findstr "\<call !gw!\>"`) do echo %%i
for /f "usebackq tokens=2 delims= " %%i in (`arp -a ^| findstr "\<!gw:~1!\>"`) do echo %%i

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