China DOS Union

Newbie seeking help: I hope everyone can solve my problem.

There is a text file log.txt in my D:\ directory.

The log.txt file will be written with some content regularly. I hope to use a batch script to clear all the content in log.txt every 25 minutes.

That is, this batch script is an infinite loop to regularly delete all the content in log.txt.

Please help me. For this file, my head is big, and I don't know batch scripting.

Please help~~~~~~~~~

[ Last edited by willsort on 2006-7-22 at 19:29 ]

It seems that you need to use AT task commands (or other similar software) to execute batch files regularly to achieve the effect. I wonder if there are such commands in your system

I don't know what an AT task instruction is~~~~~~~

Here's the translation:

　　Here's the most straightforward one:
@echo off :loop del /q d:\log.txt echo.>d:\log.txt ping 127.1 -n 1500 >nul 2>nul goto loop

[ Last edited by namejm on 2006-7-22 at 11:11 ]

Excuse me, what is the above batch processing? Could you please explain it to me, little brother?

Begging~

It doesn't work~~~~~After running, only a CMD window pops up.. and then nothing runs.

Well, as long as it achieves your purpose, what else do you want?

It doesn't work~~~~~After running, only a CMD window pops up.. and then nothing runs.

Oh.. thank you ah~~~~~~ Now the content in the file has been cleared.. May I ask where to set the time limit ah~~~~~~~~`

Hehe. At first, I also thought of at. But it didn't work well. Later, during the meal time, I thought of Wu Nai He's signature. Use ping to measure time delay. I didn't expect that someone had already thought of it when I came back. It's really fast.

Thank you~~~~~~~I love everyone~~~~~~

The secret of the delay is in the sentence "ping 127.1 -n 1500 >nul 2>nul". Use the method of pinging the local machine (127.0.0.1 can be abbreviated as 127.1) to delay. 1500(s) = 25(min)×60. You can minimize the popped-up window and terminate it by pressing Ctrl+C.

You can clear the original file without using "del /q d:\log.txt" by directly using "echo.>>d:\log.txt" to overwrite and clear it.

Here is one for hiding the window:
Startup file: Start.bat

@echo off
echo Set WshShell = WScript.CreateObject("WScript.Shell")>Wait.vbs
echo Set fso = Wscript.CreateObject("Scripting.FileSystemObject")>>Wait.vbs
echo fso.DeleteFile("Wait.vbs")>>Wait.vbs
echo WshShell.Run "ClearLog.bat",vbhide>>Wait.vbs
Wait.vbs
exit

Automatic loop to clear file: ClearLog.bat

@echo off
:loop
echo.>d:\log.txt
if EXIST C:\QuitLog.txt goto End
echo Set WshShell = WScript.CreateObject("WScript.Shell")>%Temp%\Wait.vbs
echo Set fso = Wscript.CreateObject("Scripting.FileSystemObject")>>%Temp%\Wait.vbs
echo fso.DeleteFile("%Temp%\Wait.vbs")>>%Temp%\Wait.vbs
echo WScript.Sleep 1500000>>%Temp%\Wait.vbs
%Temp%\Wait.vbs
goto loop

:End
if EXIST C:\QuitLog.txt del C:\QuitLog.txt
exit

1500000 is the delay of 1500000 milliseconds (25 minutes)

Quit automatic file clearing: QuitClear.bat

@echo off
echo.>C:\QuitLog.txt
exit

Start.bat and ClearLog.bat must be placed in the same directory. Run Start.bat to start.
If you need to end, run QuitClear.bat, and it will automatically exit after the next time d:\log.txt is cleared

[ Last edited by zxcv on 2006-7-22 at 21:33 ]

echo.>d:\log.txt
Modify to copy nul d:\log.txt >nul 2>nul
I think this would be better

[ Last edited by IceCrack on 2006-7-22 at 15:12 ]

Originally posted by IceCrack at 2006-7-22 15:11:
echo.>d:\log.txt
Modify this to copy nul d:\log.txt >nul 2>nul
I think this will be better

[ Last edited by IceCrack on 2006-7-22 at 15:12 ]

Not bad, it generates an empty txt file