Reading a value from a file in a windows batch script

Question

I'm trying to read a value from a file and use it in a subsequent command.

I have a file called AppServer.pid which contains the process id of my app server (just the number, it's not a properties file or anything like that).

The app server is hanging, so I want to take this value and pass it to the kill command. So my script will be something like

SET VALUE_FROM_FILE=AppServer.pid # or something
taskkill /pid %VALUE_FROM_FILE% /f

Is there a convenient way to do this in Windows scripting?

Answer 1

for /f %%G in (appid.txt) do (SET PID=%%G)
echo %PID%
taskkill etc here...

This might help !

Answer 2

This works:

SET /P VALUE_FROM_FILE= < AppServer.pid
taskkill /pid %VALUE_FROM_FILE% /f

The /P parameter used with SET allows you to set the value of a parameter using input from the user (or in this case, input from a file)